Abstract: Autonomous driving in open-pit mines can reduce the number of operating personnel, lower production costs and safety risks, and has become an important direction for the intelligent development of open-pit mines. However, due to the relatively conservative driving speed of mining trucks planned by current autonomous driving algorithms, there is still a certain gap in its transportation efficiency compared with manned driving. To maximize the planned speed as much as possible on the premise of not violating vehicle-road physical constraints and ensuring driving safety, a motion planning method for fixed transportation routes in open-pit mines based on integral chain dynamics and Gröbner basis is proposed. First, a refined speed constraint curve for the entire section of the fixed transportation route is established according to the kinematic characteristics of mining trucks and road conditions in open-pit mines, with comprehensive consideration of conditions such as speed limit rules, road curvature, ground adhesion, and vehicle front-wheel angle. Subsequently, the integral chain dynamics theory is used to characterize the autonomous driving motion planning problem in open-pit mines as a problem of solving a system of multivariate polynomial equations regarding the action time of force change rate. The Gröbner basis theory is applied to convert the system of multivariate polynomial equations into a parameterized regular polynomial system, and finally the motion planning problem is equivalent to the problem of solving a triangularized polynomial system. In practical deployment, only the start and end condition parameters need to be input to achieve fast iterative solution, thus obtaining a motion planning scheme that meets driving safety requirements and has smooth acceleration. This method is used for motion planning of multiple sections of a real transportation route in an open-pit mine in Inner Mongolia under different initial and terminal conditions, and feasible solutions are quickly obtained in all cases. Finally, motion planning is conducted for a 3.61 km-long continuous curved round-trip route. Compared with the current actual operation records of manned mining trucks in the mine, the average operation time is reduced by 10.7%, and the calculation time for a 20 m planning task is within 100 ms, which indicates that this method can effectively improve the operation efficiency of vehicles in open-pit mines.