Abstract: Based on the analysis of all kinds of spaces in the surgical environment of orthopaedic clinic,the set with constraint-activated functions is adopted to describe clinical spaces.With concepts of the robot occupancy space,the surgeon occupancy space,the surgical object space,the instrument occupancy space,the robot working space,the robot finite dexterity space,the error-sensitive coefficient,etc.,the content and the method for the orthopaedic robot space design are proposed under the surgical environment in the orthopaedic clinic.Through the space design,the finite dexterity space of the orthopaedic robot can be appropriately deployed which can improve the robot surgery precision,simplify the robot structure,and enhance the safety and reliability of the robot.Finally,the feasibility of the method is validated in the practice of space design for the bi-planar orthopaedic robot.