Abstract: State of the art of Parkinson's disease (PD) rehabilitation robots is summarized and the development directions of related technologies are discussed. First of all, pathological characteristics, motor symptoms, rehabilitation mechanisms and therapeutic principles are presented for Parkinson's disease in comparison with stroke. Then, a comprehensive survey on the state of the art of PD rehabilitation robots and technologies is given from aspects of upper-limb rehabilitation, lower-limb rehabilitation, tremor suppression, and severity assessment techniques, respectively. Further, the limitations of current researches are analyzed, and the future directions of robot-assisted PD rehabilitation technologies are discussed. Specifically, based on the pathological characteristics and rehabilitation principles of Parkinson's disease, it is necessary to develop PD-specific brain-muscle-limb fused rehabilitation technologies.