diff --git a/lib/fluent/plugin/out_file.rb b/lib/fluent/plugin/out_file.rb
index f0a6642208..7de4b90979 100644
--- a/lib/fluent/plugin/out_file.rb
+++ b/lib/fluent/plugin/out_file.rb
@@ -188,10 +188,6 @@ def configure(conf)
         condition = Gem::Dependency.new('', [">= 2.7.0", "< 3.1.0"])
         @need_ruby_on_macos_workaround = true if condition.match?('', RUBY_VERSION)
       end
-
-      if @need_lock && @append && @fluentd_lock_dir.nil?
-        raise Fluent::InvalidLockDirectory, "must set FLUENTD_LOCK_DIR on multi-worker append mode"
-      end
     end
 
     def multi_workers_ready?