A rotating valve system for a hydrogen engine is an apparatus that generates rotation power by combusting a hydrogen-air mixture. The apparatus includes an engine block, an at least one rotating valve assembly, a plurality of internal combustion (IC) mechanisms, and a crankshaft. The engine block is a structural base for the other components of the apparatus. The IC mechanisms convert the chemical energy of hydrogen into mechanical energy. The crankshaft receives the linear motion from the IC mechanisms and coverts the linear motion into rotational motion. The rotating valve assembly includes an intake tube and an exhaust tube, both with ports that are aligned and timed to deliver a charge of air/fuel mixture to the proper IC mechanism during the intake cycle and to scavenge the exhaust gases from the proper IC mechanism during the exhaust cycle.