A drive device includes a first drive unit and a second drive unit. A transmission unit includes a primary shaft for connection to the first drive unit, a secondary shaft, and at least one gear pair via which the primary and secondary shafts are operatively connectable to one another. Mounted in coaxial relationship to the secondary shaft is a driving gear which is operatively connected to the second drive unit, and mounted in coaxial relationship to the primary shaft is an output gear which meshes with the driving gear. A secondary-shaft coupling device can couple the driving gear directly with the secondary shaft, and a primary-shaft coupling device can couple the output gear directly with the primary shaft.