The present invention provides an inflatable swimming pool convenient for drainage, which comprises an air chamber layer and a bottom pad. The air chamber layer defines an approximate rectangle with two long sides of the rectangular air chamber layer recessed inwards. The bottom of the air chamber layer is closed at a bottom plane by the bottom pad to form a pool structure, and after water is filled between the air chamber layer and the bottom pad, the two long sides of the air chamber layer can expand outwards to form a straight rectangular pool. An accommodating chamber is further arranged in the air chamber layer. The air pump is communicated with an inner cavity of the air chamber layer through an inflation communication pipe. The inflatable swimming pool of the present invention is more convenient to use, has better drainage efficiency and can be inflated automatically.