The different trajectories of upper die have an important influence on the rotary forging of spiral bevel gears, and the trajectory of upper die is determined by the rotational speed of the inner and outer eccentric sleeves. Therefore, the change of rotational speed of eccentric sleeve in the rotary forging process with single roller causes the change of motion period and trajectory shape of rose line and helical line. For the spiral bevel gear made by material 20CrMnTiH steel, a threedimensional finite element model was established by UG, and the influences of trajectory motion period and trajectory shape changes on forming force and energy parameters, deformation uniformity, root damage factor and contact area of spiral bevel gears in the rotary forging process were studied by Deform3D in detail under the different rotational speeds of eccentric sleeve. The results show that the influences of different eccentric sleeve rotational speeds on the spiral bevel gears formed by rose line and helical line rotary forging are similar, and the period T=3 s and the speed ratio |n1/n2|=6/7 in the process of roseline and helical line rotary forging are more suitable.