The technical scheme of the invention comprises a picture superposition system and method based on transparent pictures. The technical scheme is used for loading target picture data, obtaining non-transparent picture pixel points of an assigned type picture and a picture matrix formed by combination of pixel points; gathering the non-transparent picture pixel points to obtain source pictures; loading the obtained source pictures with a label processor, and splicing the source pictures according to assigned rules to obtain an assigned area object, wherein the label processor is also used for providing register of mouse event behaviors; and carrying out traversal of the mouse event behaviors of a target picture, and carrying out corresponding processing of the picture according to the behaviors and the positions of a mouse. The beneficial effects are that the processing based on the transparent pictures is simplified, the manpower and the material resources required are saved, and the cross-platform operation can be achieved.