Ti(C,N)-based cermets were recently designed for tool applications as they offer enhanced interfacial strength. Such a cermet exhibits a typical core/rim microstructure as found in conventional cermets. To determine the possibility of using new cermet as a cutting tool, Ti(C,N) along with various carbides, nitrides, solid-solution carbonitride such as (Ti,W)(C,N), and Ni were milled together, sintered into the size of SNGN120408 and used in turning the SM45C (AISI45). Commercial WC and cermet insert of an identical size were selected to compare its cutting capability with that of the home-made cermet tool. To ensure a fair comparison of the cutting performance, the optimal machining conditions for commercial WC, cermet and home-made cermet tools were obtained using the Taguchi method. Experiments under both optimal conditions showed the excellent cutting performance of the new home-made cermet tool. It is believed that the interface between core Ti(C,N) and rim phases has been improved significantly in the new cermets.