The present disclosure provides a pressing device which includes: at least two floating heads which are arranged side by side; a positioning member connecting with each floating head and defining a position of each floating head; a cover plate positioned above each floating head; and elastic members, each elastic member being provided between the cover plate and the corresponding floating head so as to make the cover plate slide up and down relative to each floating head. The pressing device can be adapted to a step type cell or a step type battery having a certain tolerance in thickness and can ensure that every step surface of the step type cell or the step type battery is uniformly pressed, thereby improving the quality of the battery.