diff --git a/lib/fluent/plugin/in_syslog.rb b/lib/fluent/plugin/in_syslog.rb
index f982cbd0b7..ca54e26a00 100644
--- a/lib/fluent/plugin/in_syslog.rb
+++ b/lib/fluent/plugin/in_syslog.rb
@@ -95,8 +95,9 @@ def initialize
     config_param :priority_key, :string, default: nil
     desc 'The field name of the facility.'
     config_param :facility_key, :string, default: nil
-    config_param :blocking_timeout, :time, default: 0.5
+    desc "The max bytes of message"
     config_param :message_length_limit, :size, default: 2048
+    config_param :blocking_timeout, :time, default: 0.5
 
     def configure(conf)
       super
diff --git a/lib/fluent/plugin/in_udp.rb b/lib/fluent/plugin/in_udp.rb
index 5fe9dd90e8..7720ae4478 100644
--- a/lib/fluent/plugin/in_udp.rb
+++ b/lib/fluent/plugin/in_udp.rb
@@ -21,13 +21,23 @@ class UdpInput < SocketUtil::BaseInput
     Plugin.register_input('udp', self)
 
     config_set_default :port, 5160
-    config_param :body_size_limit, :size, default: 4096
+
+    desc "Deprecated parameter. Use message_length_limit instead"
+    config_param :body_size_limit, :size, default: nil, deprecated: "use message_length_limit instead."
+    desc "The max bytes of message"
+    config_param :message_length_limit, :size, default: 4096
+
+    def configure(conf)
+      super
+
+      @message_length_limit = @body_size_limit if @body_size_limit
+    end
 
     def listen(callback)
       log.info "listening udp socket on #{@bind}:#{@port}"
       @usock = SocketUtil.create_udp_socket(@bind)
       @usock.bind(@bind, @port)
-      SocketUtil::UdpHandler.new(@usock, log, @body_size_limit, callback)
+      SocketUtil::UdpHandler.new(@usock, log, @message_length_limit, callback)
     end
   end
 end
diff --git a/test/plugin/test_in_udp.rb b/test/plugin/test_in_udp.rb
index e2b2166deb..88c362f12c 100755
--- a/test/plugin/test_in_udp.rb
+++ b/test/plugin/test_in_udp.rb
@@ -32,10 +32,19 @@ def test_configure
       d = create_driver(v)
       assert_equal PORT, d.instance.port
       assert_equal k, d.instance.bind
-      assert_equal 4096, d.instance.body_size_limit
+      assert_equal 4096, d.instance.message_length_limit
     }
   end
 
+  data(
+    'message_length_limit' => 'message_length_limit 2048',
+    'body_size_limit' => 'body_size_limit 2048'
+  )
+  test 'message_length_limit/body_size_limit compatibility' do |param|
+    d = create_driver(CONFIG + param)
+    assert_equal 2048, d.instance.message_length_limit
+  end
+
   def test_time_format
     configs = {'127.0.0.1' => CONFIG}
     configs.merge!('::1' => IPv6_CONFIG) if ipv6_enabled?