To provide a drain pan of a drain pump for air conditioner which prevents drain water from hitting the drain pan by reverse rushing water when the drain pump is stopped, and from generating noises by shaking the drain pan, reduces a pump suction sound of the drain pump during operation, and also, can reduce the generation of noises at the time of starting of the drain pump.

For a drain pump 1 for an air conditioner, in an approx. upside- down conical-shaped hollow pump main body 3 where a suction port 4 which is located in a drain pan 21 is provided at the lower end, a discharging port 5 is provided at an upper side part, an impeller 17 which rotates with a gap to the inner peripheral surface of the pump main body, is rotatably provided. In this case, at least on a part being confronted with the suction port 4 of the drain pump, on drain pan 21, a soundproof member 26 is provided for the constitution.