An intake/exhaust valve control device for an internal combustion engine including a cylinder having an intake valve and an exhaust valve includes: solenoids for driving at least one of the intake valve and the exhaust valve; a battery for supplying an electric current to the solenoids, a battery state predicting unit for predicting the voltage state of the battery; and an energization start timing setting unit for setting the current carrying start timing of the battery with respect to the solenoids based on the result of the prediction by the battery state predicting unit. According to the intake/exhaust valve control device, since it is possible to obtain the amount of energization necessary for driving the solenoids at an appropriate timing, it is possible to secure the responsiveness of the solenoids.