Dijkstra algorithm has been widely used for the mobile robot path planning(MRPP). However, under the complex conditions it can not make sure that the results are correct or optimal. Though with the ant colony algorithm, the mobile robot path planning model can give the global optimal solution under certain conditions, but it needs a long time for the solution. Therefore, a fusion algorithm combining Dijkstra algorithm with ant colony algorithm is proposed. This hybrid algorithm contains the advantage of Dijkstra and ant colony algorithm to obtain the optimal MRPP in shorter time. Firstly, a suboptimal solution of the shortest path can be found with the Dijkstra fast algorithm when the robot is working. Secondly, near the suboptimal solution the working environment is accurately divided. Finally, the shortest path can be gained by the ant colony algorithm. From the simulation results, more than 90% of the tracing time of the fusion algorithm can be reduced when compared with ant colony algorithm. It is apparent that this fusion optimization algorithm not only reduces the time consumption of the ant colony algorithm, but also obtains the reliable global optimal solution.