An output prediction device for a fuel cell includes: a first acquisition circuitry configured to acquire a first required output of the fuel cell, the first required output being calculated based on a predicted vehicle speed or a predicted acceleration of a vehicle on a scheduled traveling route for the vehicle, the vehicle traveling by using the fuel cell as a dynamic power source; a second acquisition circuitry configured to acquire a second required output of the fuel cell, the second required output being required by an air-conditioning device of the vehicle; and a calculation circuitry configured to calculate a parameter correlated with a predicted output value of the fuel cell, based on the first required output and the second required output, the predicted output value being predicted as an output on the scheduled traveling route.