diff --git a/lib/groonga-query-log/command/run-regression-test.rb b/lib/groonga-query-log/command/run-regression-test.rb
index 2b5aaad5..68411a6a 100644
--- a/lib/groonga-query-log/command/run-regression-test.rb
+++ b/lib/groonga-query-log/command/run-regression-test.rb
@@ -52,6 +52,7 @@ def initialize
         @skip_finished_queries = false
         @output_query_log = false
         @stop_on_failure = false
+        @retry_on_no_response = false
         @rewrite_vector_equal = false
         @rewrite_vector_not_equal_empty_string = false
         @vector_accessors = []
@@ -199,6 +200,11 @@ def create_option_parser
                   "(#{@stop_on_failure})") do |boolean|
           @stop_on_failure = boolean
         end
+        parser.on("--[no-]retry-on-no-response",
+                  "Retry execution when the no response",
+                  "(#{@retry_on_no_response})") do |boolean|
+          @retry_on_no_response = boolean
+        end
         parser.on("--[no-]rewrite-vector-equal",
                   "Rewrite 'vector == ...' with 'vector @ ...'",
                   "(#{@rewrite_vector_equal})") do |boolean|
@@ -379,6 +385,7 @@ def tester_options
           :skip_finished_queries => @skip_finished_queries,
           :ignored_drilldown_keys => @ignored_drilldown_keys,
           :stop_on_failure => @stop_on_failure,
+          :retry_on_no_response => @retry_on_no_response,
           :rewrite_vector_equal => @rewrite_vector_equal,
           :rewrite_vector_not_equal_empty_string =>
             @rewrite_vector_not_equal_empty_string,
@@ -602,6 +609,7 @@ def initialize(old, new, options)
             options[:results_directory] || (@working_directory + "results")
           @n_clients = options[:n_clients] || 1
           @stop_on_failure = options[:stop_on_failure]
+          @retry_on_no_response = options[:retry_on_no_response]
           @options = options
           @n_ready_waits = 2
         end
@@ -699,6 +707,9 @@ def verify_server(test_log_path, query_log_path, &callback)
           if @stop_on_failure
             command_line << "--stop-on-failure"
           end
+          if @retry_on_no_response
+            command_line << "--retry-on-no-response"
+          end
           if @options[:rewrite_vector_equal]
             command_line << "--rewrite-vector-equal"
           end
diff --git a/lib/groonga-query-log/command/verify-server.rb b/lib/groonga-query-log/command/verify-server.rb
index 59de6eba..1e531801 100644
--- a/lib/groonga-query-log/command/verify-server.rb
+++ b/lib/groonga-query-log/command/verify-server.rb
@@ -201,6 +201,12 @@ def create_parser
           @options.stop_on_failure = boolean
         end
 
+        parser.on("--[no-]retry-on-no-response",
+                  "Retry execution when the no response",
+                  "(#{@options.retry_on_no_response?})") do |boolean|
+          @options.retry_on_no_response = boolean
+        end
+
         parser.on("--[no-]rewrite-vector-equal",
                   "Rewrite 'vector == ...' with 'vector @ ...'",
                   "(#{@options.rewrite_vector_equal?})") do |boolean|
diff --git a/lib/groonga-query-log/server-verifier.rb b/lib/groonga-query-log/server-verifier.rb
index 22cc4395..f6f547d9 100644
--- a/lib/groonga-query-log/server-verifier.rb
+++ b/lib/groonga-query-log/server-verifier.rb
@@ -1,4 +1,5 @@
 # Copyright (C) 2013-2018  Kouhei Sutou <kou@clear-code.com>
+# Copyright (C) 2019  Horimoto Yasuhiro <horimoto@clear-code.com>
 #
 # This library is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -170,8 +171,15 @@ def verify_command(groonga1_client, groonga2_client, command)
       command["output_type"] = "json"
       rewrite_filter(command, "filter")
       rewrite_filter(command, "scorer")
-      response1 = groonga1_client.execute(command)
-      response2 = groonga2_client.execute(command)
+
+      response1, response2 = ""
+      n_tries = 3
+      n_tries.times do
+        response1 = groonga1_client.execute(command)
+        response2 = groonga2_client.execute(command)
+        break unless @options.retry_on_no_response?
+        break if (!response1.nil? && !response2.nil?)
+      end
       compare_options = {
         :care_order => @options.care_order,
         :ignored_drilldown_keys => @options.ignored_drilldown_keys,
@@ -271,6 +279,7 @@ class Options
       attr_writer :verify_cache
       attr_accessor :ignored_drilldown_keys
       attr_writer :stop_on_failure
+      attr_writer :retry_on_no_response
       attr_writer :rewrite_vector_equal
       attr_writer :rewrite_vector_not_equal_empty_string
       attr_accessor :vector_accessors
@@ -303,6 +312,7 @@ def initialize
         @verify_cache = false
         @ignored_drilldown_keys = []
         @stop_on_failure = false
+        @retry_on_no_response = false
         @rewrite_vector_equal = false
         @rewrite_vector_not_equal_empty_string = false
         @vector_accessors = []
@@ -330,6 +340,10 @@ def stop_on_failure?
         @stop_on_failure
       end
 
+      def retry_on_no_response?
+        @retry_on_no_response
+      end
+
       def rewrite_vector_equal?
         @rewrite_vector_equal
       end