This substance adhesion simulation system includes an input unit for inputting a model of a device, and information of a presence state of a substance which may be able to adhere to the device, and a processing unit which estimates an adhesion state of the substance to the device by using the information, which is input to the input unit, and the substance is in a liquid state, a gas state, a mist state, a powder state, a dust state, or a state combining the liquid state and the mist state.