The sprocket transmission mechanism of the massage device of the present invention mainly includes: a driving box for transmitting front and rear driving shafts by a dual-shaft motor, and a synchronous output of the driving force of the two-sided driving force, and a pair of pivot shafts for positioning the ends of the driving shaft. The displacement seat is fixed on the top and bottom ends of the chair or bed, and is composed of a chain on the left and right. Among them, the driving shaft is inside the pivoting position in the displacement seat, and an active chain is sleeved. The middle section of the two driving sprocket wheels is pivotally provided with a driven sprocket； thus, the two chains are provided to enter the inside of the displacement seat respectively, and are continuously wound through the bending to form three continuous driving and driven sprocket wheels. Engagement constitutes a synchronous rotation configuration； when the drive shaft is driven to rotate, the engagement position of the sprocket on the chain is changed to be carried by the displacement seat, so that the massage element on the drive shaft forms a synchronous operation of self-propelled displacement and roll massage. As its characteristics.
