diff --git a/lib/ckb/api.rb b/lib/ckb/api.rb
index 18a2aa83..8514668d 100644
--- a/lib/ckb/api.rb
+++ b/lib/ckb/api.rb
@@ -327,12 +327,6 @@ def get_banned_addresses
       result.map { |addr| Types::BannedAddress.from_h(addr) }
     end
 
-    # @param expect_confirm_blocks [Integer]
-    def estimate_fee_rate(expect_confirm_blocks)
-      result = rpc.estimate_fee_rate(expect_confirm_blocks)
-      Types::EstimateResult.from_h(result)
-    end
-
     # @param bytes_limit [String | Integer] integer or hex number
     # @param proposals_limit [String | Integer] integer or hex number
     # @param max_version [String | Integer] integer or hex number
diff --git a/spec/ckb/api_spec.rb b/spec/ckb/api_spec.rb
index 8ac7d7a6..5dcf378d 100644
--- a/spec/ckb/api_spec.rb
+++ b/spec/ckb/api_spec.rb
@@ -311,15 +311,6 @@
     expect(result).to all(be_a(Types::BannedAddress))
   end
 
-  it "estimate fee rate" do
-    begin
-      result = api.estimate_fee_rate(4)
-      expect(result).not_to be_a Types::EstimateResult
-    rescue Exception => e
-      expect(e).to be_a CKB::RPCError
-    end
-  end
-
   context "miner APIs" do
     it "get_block_template" do
       result = api.get_block_template
diff --git a/spec/ckb/rpc_spec.rb b/spec/ckb/rpc_spec.rb
index 6cc9c7b5..3f29430f 100644
--- a/spec/ckb/rpc_spec.rb
+++ b/spec/ckb/rpc_spec.rb
@@ -264,15 +264,6 @@
     expect(result).not_to be nil
   end
 
-  it "estimate fee rate" do
-    begin
-      result = rpc.estimate_fee_rate(4)
-      expect(result).not_to be nil
-    rescue Exception => e
-      expect(e).to be_a CKB::RPCError
-    end
-  end
-
   context "miner RPCs" do
     it "get_block_template" do
       result = rpc.get_block_template