diff --git a/lib/rails_admin/support/csv_converter.rb b/lib/rails_admin/support/csv_converter.rb
index 1f71b49624..0a71f47e8e 100644
--- a/lib/rails_admin/support/csv_converter.rb
+++ b/lib/rails_admin/support/csv_converter.rb
@@ -32,6 +32,7 @@ def initialize(objects = [], schema = {})
     end
 
     def to_csv(options = {})
+      options = HashWithIndifferentAccess.new(options)
       encoding_to = Encoding.find(options[:encoding_to]) if options[:encoding_to].present?
 
       csv_string = generate_csv_string(options)