A new masonry system has been developed to improve the seismic behaviour of RC frame with masonry panels. In this system dry-stack masonry panels are built with masonry units capable of sliding in-plane of a panel. These masonry panels have reduced in-plane stiffness but increased frictional energy dissipation capacity compared with the traditional masonry panels. Under seismic or wind loads these panels do not detrimentally interfere with natural RC frame response but rather positively contribute to it mainly by increasing dumping. A cyclic test has been performed to evaluate the behaviour of this masonry system. Test results demonstrate that the new system can improve the seismic behaviour of RC frame structures with masonry panels.