With crowd logistics becoming a crucial part of the last-mile delivery challenge in many cities, continued participation of crowd workers has become an essential issue affecting the growth of the crowd logistics platform. Understanding how people are motivated to continue their participation in crowd logistics can provide some clarity as to what policies and measures should be undertaken by the industry to support its further growth. Using the Push-Pull-Mooring (PPM) theory, we developed a research model to explain the factors influencing crowd workers' participative behavior. Survey data from 455 crowd workers were analyzed using SmartPLS3.0 software. The results show monetary rewards and trust have a significant positive impact on the willingness of crowd workers to continue participating in crowd logistics, while work enjoyment from previous work and entry barriers for work have a significant negative impact. Trust plays an intermediary role between monetary incentives and crowd workers' willingness to continue participating. Based on the findings of this study, we recommend that crowd logistics platforms should offer reasonable monetary incentives and keep these under constant review, build a high degree of trust and cooperation with their crowd workers, and initiate activities geared towards promoting satisfaction at work.