With the establishment of the market economy system, the grassroots social system, which was primarily based on the unit system and supplemented by the street-residence system embedded in the planned economy system, gradually disintegrated. The grassroots social system, which is compatible with the market economy system and primarily based on the community system, emerged. At the interface of the transition period, two management patterns appeared in urban grassroots society. One is that units still play an important role in social management, acting as the main role of actual grassroots managers, and the unit system remains prominent in the post-unit era. The other is that communities have come to the forefront of grassroots social governance, having a foundational position in social governance innovation, becoming the background field for multiple subjects to play roles in grassroots governance, and gradually playing important social governance functions in various types of community forms (unit communities, commercial housing communities, etc.). Units and communities coexist, with units handling major affairs and governance matters, communities handling minor affairs and also major affairs, and more regional matters.