A joint mobilization apparatus includes a pulling unit and a power unit. The pulling unit includes a wearable member set for mounting on the patient's joint part, and a rope set connected to the wearable member set. The power unit provides power of reciprocatingly pulling the rope set, and includes a shell member, a motor, and a reciprocation mechanism connected to the motor and the rope set. The reciprocation mechanism is driven by the motor to reciprocate relative to the shell member, so as to pull the rope set to reciprocate the wearable member set and patient's joint part. By using the power unit to drive the pulling unit to pull reciprocatingly for mobilizing the patient's joint part, instead of the therapist's treatment, the therapist's burden in physical strength can be reduced. Furthermore, the joint mobilization apparatus can provide the user to execute various muscle training modes.