Abstract: Residential area, usually consisting of buildings and vegetation, is one of the dominant land use types and an important kind of habitat in the urban area. Therefore, it plays an important role in urban biodiversity conservation. Previous studies found that plant diversity abroad in urban residential areas was influenced by socioeconomic factors. However, it is not clear whether this result hold for Chinese cities which have completely different urban management regime. In this study, we investigated plant species diversity in 39 residential neighborhoods in Shanghai. Biodiversity indexes, regression analysis, and partial least square regression analysis were employed to estimate the relationships between plant diversity and socioeconomic factors of population density, house price, house age and greenspace coverage. Our results showed that socioeconomic factors did affect plant diversity in urban residential areas in Shanghai. The effects varied with plant species, population density, house price, house age, and greenspace coverage. The house age had the strongest effect on most plant taxa, then followed by population density, house price, and greenspace coverage. We tested the hypotheses of “luxury effect” and “legacy effect”, and found that they only partially explained the spatial distribution of plant taxa in Shanghai. These results could provide insights for management and conservation of plant diversity, as well as urban landscape planning and design in Shanghai.