diff --git a/velox/docs/develop/testing/fuzzer.rst b/velox/docs/develop/testing/fuzzer.rst
index 9ceade966d40..55dcca70b23d 100644
--- a/velox/docs/develop/testing/fuzzer.rst
+++ b/velox/docs/develop/testing/fuzzer.rst
@@ -219,6 +219,8 @@ Below are arguments that toggle certain fuzzer features in Expression Fuzzer:
 
 * ``--velox_fuzzer_enable_complex_types``: Enable testing of function signatures with complex argument or return types. Default is false.
 
+* ``--velox_fuzzer_enable_decimal_type``: Enable testing of function signatures with decimal argument or return type. Default is false.
+
 * ``--lazy_vector_generation_ratio``: Specifies the probability with which columns in the input row vector will be selected to be wrapped in lazy encoding (expressed as double from 0 to 1). Default is 0.0.
 
 * ``--velox_fuzzer_enable_column_reuse``: Enable generation of expressions where one input column can be used by multiple subexpressions. Default is false.
diff --git a/velox/expression/ReverseSignatureBinder.cpp b/velox/expression/ReverseSignatureBinder.cpp
index 495920e6bf1f..274d2a06480f 100644
--- a/velox/expression/ReverseSignatureBinder.cpp
+++ b/velox/expression/ReverseSignatureBinder.cpp
@@ -18,27 +18,7 @@
 
 namespace facebook::velox::exec {
 
-bool ReverseSignatureBinder::hasConstrainedIntegerVariable(
-    const TypeSignature& type) const {
-  if (type.parameters().empty()) {
-    auto it = variables().find(type.baseName());
-    return it != variables().end() && it->second.isIntegerParameter() &&
-        it->second.constraint() != "";
-  }
-
-  const auto& parameters = type.parameters();
-  for (const auto& parameter : parameters) {
-    if (hasConstrainedIntegerVariable(parameter)) {
-      return true;
-    }
-  }
-  return false;
-}
-
 bool ReverseSignatureBinder::tryBind() {
-  if (hasConstrainedIntegerVariable(signature_.returnType())) {
-    return false;
-  }
   tryBindSucceeded_ =
       SignatureBinderBase::tryBind(signature_.returnType(), returnType_);
   return tryBindSucceeded_;
diff --git a/velox/expression/ReverseSignatureBinder.h b/velox/expression/ReverseSignatureBinder.h
index 087adc4dbe77..3da800a5edbb 100644
--- a/velox/expression/ReverseSignatureBinder.h
+++ b/velox/expression/ReverseSignatureBinder.h
@@ -54,10 +54,6 @@ class ReverseSignatureBinder : private SignatureBinderBase {
   }
 
  private:
-  // Return whether there is a constraint on an integer variable in type
-  // signature.
-  bool hasConstrainedIntegerVariable(const TypeSignature& type) const;
-
   const TypePtr returnType_;
 
   // True if 'tryBind' has been called and succeeded. False otherwise.
diff --git a/velox/expression/tests/ExpressionFuzzer.cpp b/velox/expression/tests/ExpressionFuzzer.cpp
index 7cd4f5aec42b..1d5c0da4d423 100644
--- a/velox/expression/tests/ExpressionFuzzer.cpp
+++ b/velox/expression/tests/ExpressionFuzzer.cpp
@@ -624,16 +624,20 @@ bool useTypeName(
 
 bool isSupportedSignature(
     const exec::FunctionSignature& signature,
-    bool enableComplexType) {
-  // Not supporting lambda functions, or functions using decimal and
-  // timestamp with time zone types.
+    bool enableComplexType,
+    bool enableDecimalType) {
+  // When enableComplexType is disabled, not supporting complex functions.
+  const bool useComplexType = useTypeName(signature, "array") ||
+      useTypeName(signature, "map") || useTypeName(signature, "row");
+  // When enableDecimalType is disabled, not supporting decimal functions. Not
+  // supporting lambda functions, or functions using timestamp with time zone
+  // types.
   return !(
       useTypeName(signature, "opaque") ||
-      // useTypeName(signature, "long_decimal") ||
-      // useTypeName(signature, "short_decimal") ||
-      // useTypeName(signature, "decimal") ||
       useTypeName(signature, "timestamp with time zone") ||
       useTypeName(signature, "interval day to second") ||
+      (!enableDecimalType && useTypeName(signature, "decimal")) ||
+      (!enableComplexType && useComplexType) ||
       (enableComplexType && useTypeName(signature, "unknown")));
 }
 
@@ -751,10 +755,10 @@ ExpressionFuzzer::ExpressionFuzzer(
     for (const auto& signature : function.second) {
       ++totalFunctionSignatures;
 
-      if (!isSupportedSignature(*signature, options_.enableComplexTypes)) {
+      if (!isSupportedSignature(*signature, options_.enableComplexTypes, options_.enableDecimalType)) {
         continue;
       }
-      if (!(signature->variables().empty() || options_.enableComplexTypes)) {
+      if (!(signature->variables().empty() || options_.enableComplexTypes || options_.enableDecimalType)) {
         LOG(WARNING) << "Skipping unsupported signature: " << function.first
                      << signature->toString();
         continue;
@@ -894,8 +898,10 @@ ExpressionFuzzer::ExpressionFuzzer(
   sortSignatureTemplates(signatureTemplates_);
 
   for (const auto& it : signatureTemplates_) {
-    auto& returnType = it.signature->returnType().baseName();
-    auto* returnTypeKey = &returnType;
+    const auto returnType = exec::sanitizeName(
+      it.signature->returnType().baseName());
+    const auto* returnTypeKey = &returnType;
+
     if (it.typeVariables.find(returnType) != it.typeVariables.end()) {
       // Return type is a template variable.
       returnTypeKey = &kTypeParameterName;
@@ -969,7 +975,7 @@ void ExpressionFuzzer::addToTypeToExpressionListByTicketTimes(
     const std::string& funcName) {
   int tickets = getTickets(funcName);
   for (int i = 0; i < tickets; i++) {
-    typeToExpressionList_[type].push_back(funcName);
+    typeToExpressionList_[exec::sanitizeName(type)].push_back(funcName);
   }
 }
 
@@ -1243,7 +1249,7 @@ core::TypedExprPtr ExpressionFuzzer::generateExpression(
     } else {
       expression = generateExpressionFromConcreteSignatures(
           returnType, chosenFunctionName);
-      if (!expression && options_.enableComplexTypes) {
+      if (!expression && (options_.enableComplexTypes || options_.enableDecimalType)) {
         expression = generateExpressionFromSignatureTemplate(
             returnType, chosenFunctionName);
       }
diff --git a/velox/expression/tests/ExpressionFuzzer.h b/velox/expression/tests/ExpressionFuzzer.h
index 7d69832e28b9..9b7d7a3b6dc9 100644
--- a/velox/expression/tests/ExpressionFuzzer.h
+++ b/velox/expression/tests/ExpressionFuzzer.h
@@ -67,6 +67,10 @@ class ExpressionFuzzer {
     // types.
     bool enableComplexTypes = false;
 
+    // Enable testing of function signatures with decimal argument or return
+    // types.
+    bool enableDecimalType = false;
+
     // Enable generation of expressions where one input column can be used by
     // multiple subexpressions.
     bool enableColumnReuse = false;
diff --git a/velox/expression/tests/FuzzerRunner.cpp b/velox/expression/tests/FuzzerRunner.cpp
index ac741944dfa6..e947f147c685 100644
--- a/velox/expression/tests/FuzzerRunner.cpp
+++ b/velox/expression/tests/FuzzerRunner.cpp
@@ -121,6 +121,11 @@ DEFINE_bool(
     false,
     "Enable testing of function signatures with complex argument or return types.");
 
+DEFINE_bool(
+    velox_fuzzer_enable_decimal_type,
+    false,
+    "Enable testing of function signatures with decimal argument or return types.");
+
 DEFINE_bool(
     velox_fuzzer_enable_column_reuse,
     false,
@@ -168,6 +173,7 @@ ExpressionFuzzer::Options getExpressionFuzzerOptions(
   opts.enableVariadicSignatures = FLAGS_enable_variadic_signatures;
   opts.enableDereference = FLAGS_enable_dereference;
   opts.enableComplexTypes = FLAGS_velox_fuzzer_enable_complex_types;
+  opts.enableDecimalType = FLAGS_velox_fuzzer_enable_decimal_type;
   opts.enableColumnReuse = FLAGS_velox_fuzzer_enable_column_reuse;
   opts.enableExpressionReuse = FLAGS_velox_fuzzer_enable_expression_reuse;
   opts.functionTickets = FLAGS_assign_function_tickets;