Aiming at problems of poor environmental adaptability of photoelectric navigation and low accuracy of long-term positioning of inertial navigation adopted in roadheader positioning, an inertial navigation positioning method of roadheader based on zero-velocity update was put forward based on analysis of movement characteristics of roadheader. In short stopping time interval of roadheader, velocity error curve of inertial navigation system is fitted by quadratic curve, and position error curve is obtained by integration, so as to correct position measurement value of inertial navigation system. The test results show that the inertial navigation positioning accuracy of roadheader based on zero-speed update can reach centimeter-level, fluctuation range of positioning error is small, and accumulated positioning error has no obvious increasing trend with the increase of time, which meets positioning requirements of roadheader.