The utility model discloses an ultra-thin massage machine core which comprises a shell and a malaxation massage mechanism. The malaxation massage mechanism comprises a malaxation rotating shaft, a malaxation drive device and two partial pendulum type malaxation massage pieces. Two supporting bases are arranged on the shell, the ends of the malaxation rotating shaft are arranged on the supporting bases respectively, the malaxation massage pieces are close to the ends of the malaxation rotating shaft, and the malaxation drive device comprises a malaxation motor and a malaxation speed reducer. A downwards-sunken containing space is formed between the two supporting bases, and the malaxation motor is arranged on the containing space. The malaxation rotating shaft is located over the malaxation motor and the malaxation rotating shaft and the malaxation motor are arranged in a perpendicular and staggered mode. The first output end of an output shaft of the malaxation motor is connected with the malaxation rotating shaft through the malaxation speed reducer in a transmission mode. Because the malaxation rotating shaft is located over the malaxation motor and the malaxation rotating shaft and the malaxation motor are arranged in the perpendicular and staggered mode, the length of the massage machine core is effectively reduced, and the massage machine core is made to have the advantage of being small in length. A U-shaped transmission structure of the malaxation speed reducer is formed, and the ultra-thin massage machine core has the advantage of being small in size.