The main content of this work is to design and realize a building security patrol intelligent robot, which is suitable for the security work of buildings, warehouses, factories and other areas; it can automatically detect the dynamic building environment in the case of no one, assist the building intelligent security equipment, and realize the complete security system. Specific contents include: 1. Investigate and analyze the current application status of security patrol robots; 2. Comprehensive analysis of the actual environmental characteristics of the building, sorting out the functional requirements of the patrol robot applicable to the building environment; 3. According to the analysis of the functional requirements of the patrol robot, the structure of the control system is designed: 1) Design the hardware system of patrol robot, including main control system, action system, environmental monitoring hardware system and communication system; 2) Design the software system of the patrol robot to realize the functions of mobile positioning, environmental monitoring, video acquisition and active avoidance of the human body. The robot can complete the patrol task independently, or the user can complete the designated cruise in the manual mode, and the user can easily manipulate the robot through the software; 3) Test the functions of the patrol robot and demonstrate whether it meets the design requirements.