A fuel cell automobile (10) in which the battery assist amount for assisting a fuel cell stack (30) is set appropriately depending on the mode position MP and the accelerator opening variation rate delta Acc. Since it is supposed that an operator is requesting quick acceleration when delta Acc is large, the battery assist amount is increased so that sufficient acceleration feeling can be enjoyed.On contrary, since it is supposed that an operator is requesting gentle acceleration when the accelerator opening variation rate delta Acc is small, the battery assist amount is decreased to suppressacceleration thus enhancing fuel consumption. Furthermore, since it is supposed that preference is given to acceleration in sport mode, the battery assist amount is increased as compared with a case in other modes so that sufficient acceleration feeling can be attained, and since it is supposed that preference is given to fuel efficiency in economy mode, the battery assist amount is decreased as compared with a case in other modes thus improving fuel efficiency.