Turning and milling tests of hardened plain and alloy steels (JIS S55C and JIS SNCM630) with TiC added ceramic tools are conducted and compared with carbide tools. Tool wear or disintegration of cutting edges are observed precisely under various cutting conditions and obtained tool life data are analyzed in order to evaluate the cutting performance of ceramic tools in machining of hardened steels. From these experiments, excellent performance of ceramic tools in turning test is reported. Also some specific facts and suggestions are proposed for the successful use of ceramic tools in face milling of steels.