Abstract: A pressure vessel for propellants, an explosion preventing method of the same, and a manufacturing method of the same are disclosed. The pressure vessel for propellants comprises a body provided with a cylindrical portion between a forward dome and an aft dome, and has an inner space where propellants are arranged. The pressure vessel also includes an insulation layer disposed on an inner wall of the body and configured to insulate the body from the inner space when the propellants are ignited; and a nozzle mounted at the aft dome and through which combustion material from the propellants is exhausted out. The body comprises a first hybrid fiber layer which forms the cylindrical portion, the forward dome, and the aft dome, and has a mechanical property lowered at a temperature more than a specific temperature such that the forward dome and the aft dome collapse by an inner pressure when the propellants are abnormally combusted.