Biologically inspired hexapod robot’s navigation system based on INS-GPS is designed in order to meet its working surroundings and task’s demand.Centralized open-loop Kalman filter is applied in the navigation system.INS-GPS devices’output difference is the filter’s input.The position-velocity integrated measurement equation is deduced based on the robot’s locomotion performance and measurement demand.Simulation experiments are conducted under MATLAB software environment.The simulation results show that the system’s navigation precision is improved effectively.The hexapod robot can realize intelligent and real-time control based on it.