Due to the differences between development teams and the complexity, uncertainty, and dynamics of development projects, it is difficult to reasonably allocate development tasks. Considering the factors such as the uncertain capability of development teams and the uncertain operation process of development projects, the duration and cost of development projects are evaluated through simulation. The psychological factors of decision-makers are taken into account, and the prospect value of development duration and costs is calculated by the prospect theory. After that, the prospect value is taken as the fitness evaluation index, and a task-allocation optimization algorithm is constructed on the basis of NSGA-III. The case study shows that the optimization algorithms based on NSGA-III, NSGA-II, and MOEA-D can all effectively improve the allocation scheme of development tasks, and the optimization based on NSGA-III is the best.