Abstract This research presents an innovative selected maintenance model for complex systems that considers the uncertainty in maintenance time (MT) for system components with multiple repairpersons. The computational model of uncertain MT for system components is established. An imperfect maintenance model is introduced, which has many imperfect maintenance levels not only considering do nothing, minimal repair, and replacement but also considering multiple intermediate maintenance levels. Furthermore, the system components maintenance assignment algorithm with multiple repairpersons is proposed to addresses the problem of how to assign multiple maintenance tasks to multiple repairpersons in order to minimize system MT. And it is innovatively integrated into the particle swarm optimization (PSO) to solve the proposed selective maintenance model, which enables heuristic algorithm to efficiently assign the multiple maintenance tasks with multiple repairpersons. The effectiveness and advantages of the proposed model and algorithm are verified by numerical experiments.