Abstract: Under new agricultural production mode, picking robot has become an important part of intelligent agricultural equipment．In unstructured environment, visual servo control has become key technology of picking robot to obtain advantages of large amount of information and strong robustness． Combining research progress and principles of three classical visual servo control methods, advantages, disadvantages and research focus of various control methods were compared and summarized, solutions to some key problems were analyzed, visual servo control technology with strong adaptability to picking robot was put forward, and development trend of the technology was prospected．