A handheld electronic device including a lower housing, an upper housing, a touch panel, a display module, a partition, position posts, cushions, and an actuator is provided. The upper housing is above and separated from the lower housing. The touch panel is at an opening of the upper housing and connects with the upper housing. The display module is disposed in the upper housing and connected with the lower housing. The partition is between the display module and the lower housing and connected to the upper housing. The partition has position holes. The position posts are located in their corresponding position holes and connected with the display module. The cushions are located between the corresponding position post and the position hole. The actuator is disposed between the display module and the upper housing to force the upper housing to shift relative to the display module and the lower housing.