A drive axle device having the disk brake and planetary gear reducing unit at the outer end of the drive shaft and a wheel shaft outside said disk brake and gear reducing unit. The axle tube which incorporates the drive shaft terminates in a flanged portion at its outer end and encompasses the disk brake in the flanged portion. The disk is positioned on the drive shaft near the outer end thereof. Further out on the drive shaft is a sun gear which forms a part of the gear reducing unit. Also included in the latter unit are planetary gears which mesh with the sun gear, a planetary carrier for rotatably supporting the planetary gears, and a fixed ring gear which is fixed to a gear housing and meshes with the planetary gears. The gear housing is bolted to the flanged portion of the axle tube and encloses the gear reducing unit. A wheel shaft in line with the drive shaft is fixed on the planetary carrier to rotate therewith. A first bearing is between the wheel shaft and the gear housing, and a second bearing is between the planetary carrier and the gear housing.