A lunar surface complete coverage path planning method based on improved optimization of the WaveFront algorithm is proposed to address the problem of lunar rover exploration and drilling missions on the lunar surface facing complex terrain areas. The method includes the construction of passable terrain maps for complex lunar surface regions, filtering of complete coverage path points based on safety considerations, breadth-first search traversal of the map using the WaveFront algorithm, post-processing of map data, and introduction of optimization mechanisms for complete coverage path search. This method achieves complete coverage path planning for lunar rovers in complex lunar terrain areas. Experiments show that this method exhibits good adaptability to various complex terrains and achieves high success rates in achieving large coverage results.