An exoskeleton robot is kind of a man-machine system which mostly uses combination of human intelligence and machine power. These robotic systems are used for different applications such as rehabilitation, human power amplification, motion assistance, virtual reality etc. Successful operation of an exoskeleton robot depends on correct selection of design and control methodologies. This paper reviews control methodologies used in upper limb exoskeleton robots. In the review, the control methods used in the exoskeleton robots are classified into three categories: control system based on human biological signal, nonbiological signal and platform independent control system. Different types of control methods under each category are compared and reviewed.