diff --git a/lib/fluent/plugin/parser_winevt_sax.rb b/lib/fluent/plugin/parser_winevt_sax.rb
index 382740e..c3a10ca 100644
--- a/lib/fluent/plugin/parser_winevt_sax.rb
+++ b/lib/fluent/plugin/parser_winevt_sax.rb
@@ -19,7 +19,7 @@ def configure(conf)
           require 'nokogiri'
           require 'fluent/plugin/winevt_sax_document_nokogiri'
           @use_nokogiri = true
-        rescue
+        rescue LoadError => e
           if @parser == :nokogiri
             raise Fluent::ConfigError,
                   "Nokogiri is required when 'parser nokogiri' is specified, but it isn't installed. " \
diff --git a/lib/fluent/plugin/parser_winevt_xml.rb b/lib/fluent/plugin/parser_winevt_xml.rb
index 0c68952..4b2dde2 100644
--- a/lib/fluent/plugin/parser_winevt_xml.rb
+++ b/lib/fluent/plugin/parser_winevt_xml.rb
@@ -18,7 +18,7 @@ def configure(conf)
         begin
           require 'nokogiri'
           @use_nokogiri = true
-        rescue
+        rescue LoadError => e
           if @parser == :nokogiri
             raise Fluent::ConfigError,
                   "Nokogiri is required when 'parser nokogiri' is specified, but it isn't installed. " \