To prevent the occurrence of whistle noise by avoiding expansion of vibration in a pressure regulation valve system component, in a vaporizer internally equipped with a lever-type pressure regulation valve.

The vaporizer 1 introduces gas fuel to a pressure regulation chamber 2, and reduces and adjusts the pressure a prescribed pressure to deliver the gas fuel, by opening and closing a pressure regulation valve 5 provided at a fuel introducing part into the pressure regulation chamber by an action of a valve lever 6 axially supported by a holder 8. In the vaporizer, a weight application adapter 10 is fitted into a lever attachment part 41 of a valve element 4 in the pressure regulation valve 5.