There is provided an engine rotation speed control device for performing over-speed rotation prevention control to decrease an engine rotation speed if the engine rotation speed exceeds a first upper limit rotation speed. If a gear position of a transmission is a neutral state or an intermediate neutral state in which predetermined gears are not engaged with each other in the middle of a gear change operation of the transmission, a second upper limit rotation speed which is lower than the first upper limit rotation speed is set. If the engine rotation speed at the time when the gear position of the transmission is the neutral state or the intermediate neutral state is higher than the second upper limit rotation speed, the over-speed rotation prevention control is performed.