In the new stage of China's economic development, significant transformations have occurred in the mode, emphasis and speed of urban development. Enhancing the level of livelihood public service and promoting the green development of cities have emerged as the prevailing themes of contemporary urban development. Based on a theoretical model analysis, using the panel data of 281 cities in China from 2007 to 2020, this paper adopts the fixed-effect model for empirical analysis. The study revealed the following four main points. (1) The provision of livelihood public services can effectively enhance the efficiency of urban green development. After conducting a series of robustness tests, this conclusion is still valid. (2) The provision of livelihood public services only fosters the green transformation of non-resource-based cities, while its impact on resource-based cities remains non-significant. (3) The mechanism test demonstrated that livelihood public services promote green development efficiency mainly through population, innovation and producer services agglomeration. (4) The threshold effect test showed that there are differences in the nonlinear relationship between the livelihood public service level and urban green development efficiency under different threshold variables.