To solve the problem of task allocation for drone mapping in complex mountainous terrain, a unified solution for multi?drone mapping task allocation / flight path planning was proposed. Firstly, a flight path planning model was established for each mapping area based on the complexity of different terrain in mountainous areas. Then, a unified model for multi?drone mapping task allocation / flight path planning was established with the optimization objective of minimizing the mapping time and flight time between various task points of the drone, and the constraints of the drone's cruising speed and maximum task duration, etc. Finally, the multi?drone mapping task allocation unified model was solved using a distributed genetic algorithm. An experimental verification was conducted to verify the effectiveness of the algorithm, and the results showed that the distributed genetic algorithm significantly reduced the mapping time and improved the mapping efficiency. The research findings provide a new technical approach for drone mapping task allocation and play a positive role in promoting the development of drone mapping.