The invention relates to a special massage actuator for a back and chest united massage robot. The special massage actuator comprises a casing, lock screws and massage actuator bodies mounted in the casing, wherein the massage actuator bodies are uniformly arranged in the peripheral direction of the casing and are fixed with the inner side wall of the casing through the lock screws; each massage actuator body comprises a fixed seat, rotary hinges, driving oscillating bars, servo motors, a universal hinge, driven oscillating bars, spherical hinges, a moving platform and massage heads. The massage actuator adopts six-degrees-of-freedom delta parallel mechanisms, can realize movement in six degrees-of-freedom directions including three translation direction and three rotation directions in the space, and has high movement flexibility, small movement requirement for space and good movement stability, and the massage effect of the massage actuator is more obvious with application of the six-degrees-of-freedom delta parallel mechanisms to the massage actuator.