The invention provides a three-degree-of-freedom motion simulator. The three-degree-of-freedom motion simulator comprises a fixed platform, a movable platform, three parallel movement branches which are arranged between the fixed platform and the movable platform, and driving mechanisms corresponding to the movement branches in a one-to-one mode. Each movement branch comprises a first rotating pair arranged on the fixed platform, a first connecting rod connected with the first rotating pair, a second rotating pair arranged on the movable platform and a second connecting rod connected with thesecond rotating pair. The first connecting rod and the second connecting rod are connected through a spherical hinge pair. Each driving mechanism corresponding to each movement branch is arranged on the fixed platform and used for driving the first connecting rod to swing around the first rotating pair. The first rotating pair and the second rotating pair are symmetrical respect to a first plane,wherein the first plane is a plane passing through the center point of the spherical hinge pair of the three movement branches. According to the three-degree-of-freedom motion simulator, the movementof two-rotation and one-movement on the movable platform is realized, thus achieving a high compression ratio and less occupied space.