diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index 13fb6e3d93b..a80668a4524 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -3,6 +3,7 @@ Yii Framework 2 Change Log
 
 2.0.50 under development
 ------------------------
+- Bug #20045: Fix type `boolean` in `MySQL` (terabytesoftw)
 - Bug #20040: Fix type `boolean` in `MSSQL` (terabytesoftw)
 - Bug #20005: Fix `yii\console\controllers\ServeController` to specify the router script (terabytesoftw)
 - Bug #19060: Fix `yii\widgets\Menu` bug when using Closure for active item and adding additional tests in `tests\framework\widgets\MenuTest` (atrandafir)
diff --git a/framework/db/mysql/Schema.php b/framework/db/mysql/Schema.php
index fa2270eb77d..666279e3b98 100644
--- a/framework/db/mysql/Schema.php
+++ b/framework/db/mysql/Schema.php
@@ -279,7 +279,7 @@ protected function loadColumnSchema($info)
                     if (isset($values[1])) {
                         $column->scale = (int) $values[1];
                     }
-                    if ($column->size === 1 && $type === 'bit') {
+                    if ($column->size === 1 && ($type === 'tinyint' || $type === 'bit')) {
                         $column->type = 'boolean';
                     } elseif ($type === 'bit') {
                         if ($column->size > 32) {
diff --git a/tests/framework/db/mysql/SchemaTest.php b/tests/framework/db/mysql/SchemaTest.php
index 4e602a317ea..82342419a8c 100644
--- a/tests/framework/db/mysql/SchemaTest.php
+++ b/tests/framework/db/mysql/SchemaTest.php
@@ -228,9 +228,13 @@ public function getExpectedColumns()
             ]
         );
 
+        $columns['bool_col']['type'] = 'boolean';
+        $columns['bool_col']['phpType'] = 'boolean';
+        $columns['bool_col2']['type'] = 'boolean';
+        $columns['bool_col2']['phpType'] = 'boolean';
+
         if (version_compare($version, '5.7', '<')) {
             $columns['int_col3']['phpType'] = 'string';
-
             $columns['json_col']['type'] = 'text';
             $columns['json_col']['dbType'] = 'longtext';
             $columns['json_col']['phpType'] = 'string';
diff --git a/tests/framework/db/mysql/type/BooleanTest.php b/tests/framework/db/mysql/type/BooleanTest.php
new file mode 100644
index 00000000000..bc9d307a78d
--- /dev/null
+++ b/tests/framework/db/mysql/type/BooleanTest.php
@@ -0,0 +1,249 @@
+<?php
+/**
+ * @link https://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license https://www.yiiframework.com/license/
+ */
+
+namespace yiiunit\framework\db\mysql\type;
+
+use yii\db\mysql\Schema;
+use yiiunit\framework\db\DatabaseTestCase;
+
+/**
+ * @group db
+ * @group mysql
+ */
+class BooleanTest extends DatabaseTestCase
+{
+    protected $driverName = 'mysql';
+
+    public function testBoolean()
+    {
+        $db = $this->getConnection(true);
+        $schema = $db->getSchema();
+        $tableName = '{{%boolean}}';
+
+        if ($db->getTableSchema($tableName)) {
+            $db->createCommand()->dropTable($tableName)->execute();
+        }
+
+        $db->createCommand()->createTable(
+            $tableName,
+            [
+                'id' => $schema->createColumnSchemaBuilder(Schema::TYPE_PK),
+                'bool_col_tinyint' => $schema->createColumnSchemaBuilder(Schema::TYPE_BOOLEAN),
+                'bool_col_bit' => $schema->createColumnSchemaBuilder('bit', 1),
+            ]
+        )->execute();
+
+        // test type `boolean`
+        $columnBoolColTinyint = $db->getTableSchema($tableName)->getColumn('bool_col_tinyint');
+        $this->assertSame('boolean', $columnBoolColTinyint->phpType);
+
+        $columnBoolColBit = $db->getTableSchema($tableName)->getColumn('bool_col_bit');
+        $this->assertSame('boolean', $columnBoolColBit->phpType);
+
+        // test value `false`
+        $db->createCommand()->insert($tableName, ['bool_col_tinyint' => false, 'bool_col_bit' => false])->execute();
+        $boolValues = $db->createCommand("SELECT * FROM $tableName WHERE id = 1")->queryOne();
+        $this->assertEquals(0, $boolValues['bool_col_tinyint']);
+        $this->assertEquals(0, $boolValues['bool_col_bit']);
+
+        // test php typecast
+        $phpTypeCastBoolColTinyint = $columnBoolColTinyint->phpTypecast($boolValues['bool_col_tinyint']);
+        $this->assertFalse($phpTypeCastBoolColTinyint);
+
+        $phpTypeCastBoolColBit = $columnBoolColBit->phpTypecast($boolValues['bool_col_bit']);
+        $this->assertFalse($phpTypeCastBoolColBit);
+
+        // test value `true`
+        $db->createCommand()->insert($tableName, ['bool_col_tinyint' => true, 'bool_col_bit' => true])->execute();
+        $boolValues = $db->createCommand("SELECT * FROM $tableName WHERE id = 2")->queryOne();
+        $this->assertEquals(1, $boolValues['bool_col_tinyint']);
+        $this->assertEquals(1, $boolValues['bool_col_bit']);
+
+        // test php typecast
+        $phpTypeCastBoolColTinyint = $columnBoolColTinyint->phpTypecast($boolValues['bool_col_tinyint']);
+        $this->assertTrue($phpTypeCastBoolColTinyint);
+
+        $phpTypeCastBoolColBit = $columnBoolColBit->phpTypecast($boolValues['bool_col_bit']);
+        $this->assertTrue($phpTypeCastBoolColBit);
+    }
+
+    public function testBooleanWithValueInteger()
+    {
+        $db = $this->getConnection(true);
+        $schema = $db->getSchema();
+        $tableName = '{{%boolean}}';
+
+        if ($db->getTableSchema($tableName)) {
+            $db->createCommand()->dropTable($tableName)->execute();
+        }
+
+        $db->createCommand()->createTable(
+            $tableName,
+            [
+                'id' => $schema->createColumnSchemaBuilder(Schema::TYPE_PK),
+                'bool_col_tinyint' => $schema->createColumnSchemaBuilder(Schema::TYPE_BOOLEAN),
+                'bool_col_bit' => $schema->createColumnSchemaBuilder('bit', 1),
+            ]
+        )->execute();
+
+        // test type `boolean`
+        $columnBoolColTinyint = $db->getTableSchema($tableName)->getColumn('bool_col_tinyint');
+        $this->assertSame('boolean', $columnBoolColTinyint->phpType);
+
+        $columnBoolColBit = $db->getTableSchema($tableName)->getColumn('bool_col_bit');
+        $this->assertSame('boolean', $columnBoolColBit->phpType);
+
+        // test value `0`
+        $db->createCommand()->insert($tableName, ['bool_col_tinyint' => 0, 'bool_col_bit' => 0])->execute();
+        $boolValues = $db->createCommand("SELECT * FROM $tableName WHERE id = 1")->queryOne();
+        $this->assertEquals(0, $boolValues['bool_col_tinyint']);
+        $this->assertEquals(0, $boolValues['bool_col_bit']);
+
+        // test php typecast
+        $phpTypeCastBoolColTinyint = $columnBoolColTinyint->phpTypecast($boolValues['bool_col_tinyint']);
+        $this->assertFalse($phpTypeCastBoolColTinyint);
+
+        $phpTypeCastBoolColBit = $columnBoolColBit->phpTypecast($boolValues['bool_col_bit']);
+        $this->assertFalse($phpTypeCastBoolColBit);
+
+        // test value `1`
+        $db->createCommand()->insert($tableName, ['bool_col_tinyint' => 1, 'bool_col_bit' => 1])->execute();
+        $boolValues = $db->createCommand("SELECT * FROM $tableName WHERE id = 2")->queryOne();
+        $this->assertEquals(1, $boolValues['bool_col_tinyint']);
+        $this->assertEquals(1, $boolValues['bool_col_bit']);
+
+        // test php typecast
+        $phpTypeCastBoolColTinyint = $columnBoolColTinyint->phpTypecast($boolValues['bool_col_tinyint']);
+        $this->assertTrue($phpTypeCastBoolColTinyint);
+
+        $phpTypeCastBoolColBit = $columnBoolColBit->phpTypecast($boolValues['bool_col_bit']);
+        $this->assertTrue($phpTypeCastBoolColBit);
+    }
+
+    public function testBooleanWithValueNegative()
+    {
+        $db = $this->getConnection(true);
+        $schema = $db->getSchema();
+        $tableName = '{{%boolean}}';
+
+        if ($db->getTableSchema($tableName)) {
+            $db->createCommand()->dropTable($tableName)->execute();
+        }
+
+        $db->createCommand()->createTable(
+            $tableName,
+            [
+                'id' => $schema->createColumnSchemaBuilder(Schema::TYPE_PK),
+                'bool_col_tinyint' => $schema->createColumnSchemaBuilder(Schema::TYPE_BOOLEAN),
+                'bool_col_bit' => $schema->createColumnSchemaBuilder('bit', 1),
+            ]
+        )->execute();
+
+        // test type `boolean`
+        $columnBoolColTinyint = $db->getTableSchema($tableName)->getColumn('bool_col_tinyint');
+        $this->assertSame('boolean', $columnBoolColTinyint->phpType);
+
+        $columnBoolColBit = $db->getTableSchema($tableName)->getColumn('bool_col_bit');
+        $this->assertSame('boolean', $columnBoolColBit->phpType);
+
+        // test value `-1`
+        $db->createCommand()->insert($tableName, ['bool_col_tinyint' => -1, 'bool_col_bit' => -1])->execute();
+        $boolValues = $db->createCommand("SELECT * FROM $tableName WHERE id = 1")->queryOne();
+
+        $this->assertEquals(1, $boolValues['bool_col_tinyint']);
+        $this->assertEquals(1, $boolValues['bool_col_bit']);
+
+        // test php typecast
+        $phpTypeCastBoolColTinyint = $columnBoolColTinyint->phpTypecast($boolValues['bool_col_tinyint']);
+        $this->assertTrue($phpTypeCastBoolColTinyint);
+
+        $phpTypeCastBoolColBit = $columnBoolColBit->phpTypecast($boolValues['bool_col_bit']);
+        $this->assertTrue($phpTypeCastBoolColBit);
+    }
+
+    public function testBooleanWithValueNull()
+    {
+        $db = $this->getConnection(true);
+        $schema = $db->getSchema();
+        $tableName = '{{%boolean}}';
+
+        if ($db->getTableSchema($tableName)) {
+            $db->createCommand()->dropTable($tableName)->execute();
+        }
+
+        $db->createCommand()->createTable(
+            $tableName,
+            [
+                'id' => $schema->createColumnSchemaBuilder(Schema::TYPE_PK),
+                'bool_col_tinyint' => $schema->createColumnSchemaBuilder(Schema::TYPE_BOOLEAN),
+                'bool_col_bit' => $schema->createColumnSchemaBuilder('bit', 1),
+            ]
+        )->execute();
+
+        // test type `boolean`
+        $columnBoolColTinyint = $db->getTableSchema($tableName)->getColumn('bool_col_tinyint');
+        $this->assertSame('boolean', $columnBoolColTinyint->phpType);
+
+        $columnBoolColBit = $db->getTableSchema($tableName)->getColumn('bool_col_bit');
+        $this->assertSame('boolean', $columnBoolColBit->phpType);
+
+        // test value `null`
+        $db->createCommand()->insert($tableName, ['bool_col_tinyint' => null, 'bool_col_bit' => null])->execute();
+        $boolValues = $db->createCommand("SELECT * FROM $tableName WHERE id = 1")->queryOne();
+
+        $this->assertNull($boolValues['bool_col_tinyint']);
+        $this->assertNull($boolValues['bool_col_bit']);
+
+        // test php typecast
+        $phpTypeCastBoolColTinyint = $columnBoolColTinyint->phpTypecast($boolValues['bool_col_tinyint']);
+        $this->assertNull($phpTypeCastBoolColTinyint);
+
+        $phpTypeCastBoolColBit = $columnBoolColBit->phpTypecast($boolValues['bool_col_bit']);
+        $this->assertNull($phpTypeCastBoolColBit);
+    }
+
+    public function testBooleanWithValueOverflow()
+    {
+        $db = $this->getConnection(true);
+        $schema = $db->getSchema();
+        $tableName = '{{%boolean}}';
+
+        if ($db->getTableSchema($tableName)) {
+            $db->createCommand()->dropTable($tableName)->execute();
+        }
+
+        $db->createCommand()->createTable(
+            $tableName,
+            [
+                'id' => $schema->createColumnSchemaBuilder(Schema::TYPE_PK),
+                'bool_col_tinyint' => $schema->createColumnSchemaBuilder(Schema::TYPE_BOOLEAN),
+                'bool_col_bit' => $schema->createColumnSchemaBuilder('bit', 1),
+            ]
+        )->execute();
+
+        // test type `boolean`
+        $columnBoolColTinyint = $db->getTableSchema($tableName)->getColumn('bool_col_tinyint');
+        $this->assertSame('boolean', $columnBoolColTinyint->phpType);
+
+        $columnBoolColBit = $db->getTableSchema($tableName)->getColumn('bool_col_bit');
+        $this->assertSame('boolean', $columnBoolColBit->phpType);
+
+        // test value `2`
+        $db->createCommand()->insert($tableName, ['bool_col_tinyint' => 2, 'bool_col_bit' => 2])->execute();
+        $boolValues = $db->createCommand("SELECT * FROM $tableName WHERE id = 1")->queryOne();
+
+        $this->assertEquals(1, $boolValues['bool_col_tinyint']);
+        $this->assertEquals(1, $boolValues['bool_col_bit']);
+
+        // test php typecast
+        $phpTypeCastBoolColTinyint = $columnBoolColTinyint->phpTypecast($boolValues['bool_col_tinyint']);
+        $this->assertTrue($phpTypeCastBoolColTinyint);
+
+        $phpTypeCastBoolColBit = $columnBoolColBit->phpTypecast($boolValues['bool_col_bit']);
+        $this->assertTrue($phpTypeCastBoolColBit);
+    }
+}