A nitrogen-containing sintered alloy includes at least 75 and not more than 95 percent by weight of a hard phase containing Ti, a group 6A metal and WC in a prescribed composition, and at least 5 and not more than 25 percent by weight of a binder phase containing Ni, Co and unavoidable impurities. The alloy contains at least 5 and not more than 60 percent by weight of a carbide, nitride or carbonitride of Ti, and at least 30 and not more than 70 percent by weight of a carbide of a metal belonging to the group 6A of the periodic table. The atomic ratio of nitrogen/(carbon+nitrogen) in the hard phase is at least 0.2 and less than 0.5. The alloy includes a soft layer containing a binder phase metal and WC at its outermost surface, and includes a layer that hardly contains any of the hard phase containing WC in a region immediately under the soft layer, with a thickness of at least 3 .mu.m and not more than 30 .mu.m. A nitrogen-containing sintered alloy with such a composition can be employed as a cutting tool having a high reliability even without a surface coating and even for working under conditions causing strong thermal shock.