Abstract: The agricultural new quality productivity is a practical requirement for agricultural modernization. Comprehensive agricultural socialized services differ from traditional single services, covering all production links and providing robust support for their development. Based on panel data of 30 provincial-level regions in China from 2012 to 2023, this research empirically explored the impacts of comprehensive agricultural socialized services on the agricultural new quality productivity and its underlying mechanisms. The results showed that: Firstly, comprehensive agricultural socialized services directly promoted the development of the agricultural new quality productivity by enhancing laborer skills, optimizing the allocation of labor resources, and improving the utilization level of labor objects; Secondly, these services indirectly drove the growth of the agricultural new quality productivity by boosting agricultural efficiency, technological advancement, innovation-driven development, and scale operations; Thirdly, comprehensive agricultural socialized services exhibited significant positive spatial spillover effects in neighboring regions. Accordingly, the following recommendations are proposed: Establish a multi-level and all-round socialized service system, strengthen technological penetration and the coordination of various factors; Deepen the market-oriented reform of land management rights to unleash economies of scale; Enhance cross-regional service network collaboration to amplify spatial spillover effects.