Equipment maintenance tasks assignment problem is a typical multi-constraint/multi-objective nonlinear programming problem and it cannot be solved by conventional methods. This paper proposed a constraint multi-objective particle swarm optimization(CMOPSO)algorithm to solve the problem. Simulation results show that the CMOPSO algorithm is an effective one that has strong convergence optimization abilities for all different parameters and constraint conditions, and it can quickly produce a large number of optimal decision-making plans, so it is important to make optimized objective quantitative decision for equipment maintenance tasks assignment problem.