RPM Fusion provides software that the Fedora Project or Red Hat doesn't want to ship. That software is provided as precompiled RPMs for all current Fedora versions and Red Hat Enterprise Linux 5 and 6.
You need to enable EPEL on RHEL 5 & 6 or compatible distributions like CentOS before you enable RPM Fusion for EL
http://fedoraproject.org/wiki/EPEL/FAQ#howtouse
su -c 'yum localinstall --nogpgcheck \ http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm \ http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm' |
su -c 'yum localinstall --nogpgcheck \ http://download1.rpmfusion.org/free/el/updates/6/i386/rpmfusion-free-release-6-1.noarch.rpm \ http://download1.rpmfusion.org/nonfree/el/updates/6/i386/rpmfusion-nonfree-release-6-1.noarch.rpm' |
Reference : http://rpmfusion.org/Configuration