According to the method of forming a titanium nitride film, first, an inside of a reaction pipe accommodating a semiconductor wafer is heated up to 200° C. to 350° C. by using a temperature increasing heater. Then, the titanium nitride film is formed on the semiconductor wafer by supplying a film forming gas including a titanium raw material into the reaction pipe. Methylcyclopentadienyl tris(dimethylamino)titanium that does not include a chlorine atom and includes titanium is used as the titanium raw material.