Abstract: A non-road mobile machinery (NRMM) is provided and includes a fuel storage device, a fuel supply device, a vapor adsorption device, and an engine body. The vapor adsorption device is provided with an air vent communicated to the atmosphere. A vapor discharge hole of the fuel storage device is communicated to an adsorption vent of the vapor adsorption device. The NRMM also includes a valve mechanism connected between a desorption vent of the vapor adsorption device and an intake channel of the engine body. The valve mechanism is conducted with the working of the engine body and blocked with the stop of the engine body. The NRMN improves the evaporation emission performance of the NRMM when compared to the prior art and solves the problem that the evaporation emissions of the NRMM in the prior art are prone to exceed the standard.