diff --git a/xCAT-client/xCAT-client.spec b/xCAT-client/xCAT-client.spec
index e3e910f45..10e3b1bd7 100644
--- a/xCAT-client/xCAT-client.spec
+++ b/xCAT-client/xCAT-client.spec
@@ -29,7 +29,7 @@ Requires: cpio
 
 # fping or nmap is needed by pping (in case xCAT-client is installed by itself on a remote client)
 %ifos linux
-Requires: nmap perl-XML-Simple perl-XML-Parser perl-Sys-Syslog perl-Text-Balanced perl-JSON
+Requires: nmap perl-XML-Simple perl-XML-Parser perl-Sys-Syslog perl-Text-Balanced perl-JSON perl-Expect
 %else
 Requires: expat
 %endif