The invention discloses a device and method for pressing rubber joints to an electric motor. The device comprises a bottom plate, a pressing block, a pressing sleeve, a first guide plate, a second guide plate, a clamping plate and a guide bar, wherein the bottom plate, the first guide plate, the second guide plate and the clamping plate are sequentially arranged in spaced and coaxial modes; the guide bar is arranged in the bottom plate, the first guide plate, the second guide plate and the clamping plate in a penetrating mode; a space for containing rubber joint installation holes is reserved between the second guide plate and the clamping plate; the pressing block is arranged in the position, facing one side of the bottom plate, of the first guide plate; the pressing sleeve is arranged in the through hole of the first guide plate in a penetrating mode and makes contact with the pressing block; and the pressing sleeve is provided with inner holes used for containing the flat portions of one end of the rubber joints. When the joints are to be pressed, a stress application mechanism arranged between the bottom plate and the first guide plate is used for transferring pressing force to the rubber joints sequentially through the pressing block and the pressing sleeve, the pressing block, the pressing sleeve and the first guide plate move towards the side where the second guide plate is located, and accordingly the rubber joints are pressed into the rubber joint installation holes. The device and method can achieve the technical purpose of directly pressing the rubber joints onto the electric motor.