The invention discloses an internal and external dual-drive rotary table bearing assembly machine. The machine mainly comprises a frame (1), an outer gear rotary table (2), an inner gear rotary table (3), a movable seat (4), a variable frequency motor (5), a precise planetary reducer (6), a torque sensor (7), a transmission shaft (8), a driving gear (9), a fixed pin (10), an outer telescopic arm (12), an outer drive pin (13), an inner telescopic arm (14) and an inner drive pin (15), wherein the outer gear rotary table (2) and the inner gear rotary table (3) are arranged on the frame (1); and the variable frequency motor (5), the precise planetary reducer (6), the torque sensor (7), the transmission shaft (8) and the driving gear (9) are arranged on the movable seat (4). The internal and external dual-drive rotary table bearing assembly machine has a compact structure, a small floor space and a wide application range and is convenient for internal and external transmission and switchover; and by the machine, the problem of the assembly of a rotary table bearing with the diameter of more than 4 meters is solved, the labor intensity of assembly workers is reduced and working efficiency is improved.