diff --git a/sdformat.spec b/sdformat.spec
index e95c5c7..4554f4d 100644
--- a/sdformat.spec
+++ b/sdformat.spec
@@ -26,6 +26,7 @@ BuildRequires:  ignition-math-devel >= 4
 BuildRequires:  ruby-devel >= 1.9
 BuildRequires:  /usr/bin/ruby
 BuildRequires:  rubygem-multi_xml
+BuildRequires:  rubygem-rexml
 BuildRequires:	texlive-refman
 BuildRequires:	tinyxml-devel
 BuildRequires:	urdfdom-devel