To provide a multiple-disk brake device having excellent assembling performance capable of easily modifying a vehicle employing a single disk brake to a vehicle equipped with a multiple-disk brake.

The multiple-disk brake device includes a fixed disk 22 and a movable disk 24. In this case, a disk housing is provided which has parallel flanges formed at the peripheral part of the fixing surface of the disk housing to a hub, and a ventilation passage formed between the flanges, the fixed disk is attached to one flange of the disk housing, a pin parallel to a hub shaft is arranged between the parallel flanges, and the movable disk slidable by using the pin as a slide guide is attached to the periphery of the disk housing.