To address the new issues faced in protecting the rights and interests of workers in new employment forms, China has begun to set up a rights protection system for them. According to the theory of incremental institutional change within new institutionalism, the labor rights protection system in China is undergoing "accumulative" changes, incorporating many new rules. Protecting workers' rights is the foundation of trade unions' existence and its core responsibility. In the process of "accumulative" changes in the rights protection system, the trade union should clarify its role and positioning, intervening as the main drivers of institutional construction. To address issues in legal, occupational, and organizational protections during setting-up rights protection system for workers in new employment forms, this study suggests that the trade unions, as the primary driving force, should actively promote the establishment of a legal framework for protecting rights of workers in new employment forms from the outset, directly advance the improvement of occupational protection system for them, continuously innovate methods to expand the union's coverage of workers in new employment forms and enhance the quality of rights protection services to ensure organizational support for them.