Unmanned Aerial Vehicle （UAV） swarm path planning and task allocation are the cores of UAV swarm rescue applications. However， traditional methods solve path planning and task allocation separately， resulting in uneven resource allocation. In order to solve the above problem， combined with the physical attributes and application environmental factors of UAV swarm， the Ant Colony Optimization （ACO） was improved， and a Joint Parallel ACO （JPACO） was proposed. Firstly， the pheromone was updated by the hierarchical pheromone enhancement coefficient mechanism to improve the performance of JPACO task allocation balance and energy consumption balance. Secondly， the path balance factor and dynamic probability transfer factor were designed to optimize the ant colony model， which is easy to fall into local convergence， so as to improve the global search capability of JPACO. Finally， the cluster parallel processing mechanism was introduced to reduce the time consumption of JPACO operation. JPACO was compared with Adaptive Dynamic ACO （ADACO）， Scanning Motion ACO （SMACO）， Greedy Strategy ACO （GSACO） and Intersecting ACO （IACO） in terms of optimal path， task allocation balance， energy consumption balance and operation time on the open dataset CVRPLIB. Experimental results show that the average value of the optimal paths of JPACO is 7.4% and 16.3% lower than of IACO and ADACO respectively in processing small-scale operations. Compared with GSACO and ADACO， JPACO has the solution time reduced by 8.2% and 22.1% in large-scale operations. It is verified that JPACO can improve the optimal path when dealing with small-scale operations， and is obviously superior to the comparison algorithms in terms of task allocation balance， energy consumption balance， and operation time consumption when processing large-scale operations.