Urban Green Space (UGS) plays a crucial socio-cultural role in improving the quality of life. Assessment of quantity, quality, and accessibility determines whether the UGS are important social benefits. The travel preference of urban residents is a good indicator for the social relevance of UGS. This study integrates remote sensing and geographic big data to quantitatively analyze and evaluate the social benefits of urban green space. We propose a Green Social Benefit Index (GSBI) based on remote sensing retrieval and classification of urban green space. The GSBI is combined with the data on population mobility to investigate the influence of urban green space on residents’ behavior. The results show that urban residents prefer to move around in places with a higher quantity and quality of urban green space. The magnitude of the influence of urban green spatial features on population heat difference shows that accessibility > quantity > quality. The social benefits of urban green space are higher in middle centers compared to urban centers and city borders. The relationship between urban mobility and urban green space may suggest how to improve the distribution of green space in urban areas. This study could be a reference for the government planning department.