To provide a geared transmission device for an automatic transmission in which the center boss of an oil pump for installing fast a sun gear of a decelerative epicyclic gearing set laid parallel with the oil pump is shortened to heighten the stiffness, whereby it is possible to avoid scuffing etc. without enlarging the diameter.

The geared transmission device for the automatic transmission is structured so that the decelerative epicyclic gearing set G1 is installed on an input shaft 1, a direct coupling clutch C3 is installed in such a way as surrounding the gearing set G1, and that the input rotation is decelerated by G1 and transmitted to a transmitting mechanism at the rear stage while the input rotation is transmitted unchangedly by the clutch C3 to the transmitting mechanism at the rear stage. The sun gear S1 is fitted on the center boss 6a protruding to the back of a pump cover 6, and a ring gear R1 is coupled with the periphery of a flange 10 extending outward in the radial direction from the input shaft 1, and a carrier PC1 is coupled with a hollow shaft 9 by a member 53. A clutch drum 11 surrounding the ring gear R1 is installed at the front extremity of an intermediate shaft 4, and a clutch pack 12 is provided in spline fitting in the inside surface of the drum and on the periphery of the ring gear R1.