The invention discloses an alloy coal mining bit for coal excavating. The alloy coal mining bit comprises a tooth handle and a tooth tip, wherein the tooth handle is arranged on the lower part of the tooth tip; the tooth handle is a cylindrical tooth handle; the tooth tip consists of a cone, a cylinder and a circular truncated cone, wherein the cone is arranged on the upper part of the cylinder; the circular truncated cone is arranged on the lower part of the cylinder; a joint of the circular truncated cone and the cylindrical tooth handle is provided with a transition circular arc with the radius of 6.0mm; a conical surface angle a of the cone is 75 degrees; a plurality of convex threads which are consistent in turning direction are arranged on the head part of the cone; concave threads which are consistent in turning direction are formed among the convex threads; rotary threads are arranged on the side surface of the cylindrical tooth handle. The alloy coal mining bit for the coal excavating, disclosed by the invention, is reasonable in structural design, high in qualification rate during production, long in service life and capable of being applied to a mechanical alloy coal mining bit of a coal excavator to improve the production efficiency and increase economic benefits.