From the perspective of multidimensional poverty theory, this paper takes the low-income population in District J of Shanghai as the sample for analysis, and explores six dimensions of poverty, i.e., income, health, education, employment, social participation, and whether there are children in the family, and divides the population covered by subsistence allowances into three levels of poverty: high, moderate and low. We find that: (1) 71% of individuals suffer from poverty at moderate levels or above; (2) There is a clear trend of "cluster disadvantage" at high poverty levels among families with children; (3) Women, especially women without registered resident status in Shanghai, are particularly vulnerable to poverty. These "silent minorities" should be the targets of priority intervention for social assistance; (4) From a geographical perspective, areas with high poverty intensity tend to be "concentrated and connected" in space. (5) In terms of service strategies, according to the poverty intensity which can be divided into three levels of "high, moderate and low," this article proposes four types of assistance services: "general preventive, basic living needs ensured, supportive and development-oriented, and urgent protective," in order to maximize the use of limited welfare resources for the best benefits of the most group in need.