Unit attached green space is an essential component of urban green space. By opening and sharing unit attached green spaces, it can effectively supplement the shortage of urban public green space and improve the quality of the urban living environment. This article focuses on the unit attached green spaces within the main urban area and five major new cities of Shanghai. By analyzing the interpretation vector data of green forest land, satellite imagery data of Shanghai, and POI hotspot data, establish Shanghai unit attached vector database and conduct spatial feature analysis and suitability evaluation for opening and sharing, screen and identify 6 273 potential unit attached green space of open sharing with a total area of approximately 5 159.35 hm2. Select priority open areas such as the Inner Ring Road and the connecting regions of one river and one river, and identify 241 unit-attached green space with high suitability for opening within the priority open areas. The research believes that the start and sharing of the unit attached green space in Shanghai has excellent potential and high implementation efficiency. Opening and sharing can effectively increase the shared green space, improve the service coverage of urban green space, and optimize the urban greening layout.