To provide a four-cycle engine in a solenoid open/closed valve system where intake and exhaust valves of the four-cycle engine are digitally controlled.

The four-cycle engine adopts the solenoid open/closed valve system where the intake and exhaust valves of the four-cycle engine are digitally controlled. Thus, the valve can be freely controlled to be open/closed, and an adequate valve timing can be created at any engine speed (in a low-to-high speed region).