Abstract: The concept of "new quality productivity" serves as a core driving force behind the current economic transformation in China. As a multidimensional concept, the continuous deepening of its theory and practice provides new ideas and methods for sustainable development, both in China and globally. This paper constructs a theoretical analysis framework concerning the relationship between industrial agglomeration and new quality productivity on export technological complexity, along with relevant hypotheses. The analysis theoretically demonstrates that both industrial agglomeration and new quality productivity significantly influence export technological complexity, and their synergistic effect can collaboratively enhance the complexity of exports.Based on the connotation of new quality productivity, this paper develops a comprehensive evaluation system encompassing four dimensions: production materials, production objects, production levels, and production factors, to derive a comprehensive score for new quality productivity. Following the analysis of the roles of industrial agglomeration and new quality productivity on export technological complexity, this paper further constructs an appropriate spatial econometric model to verify the relationship between export technological complexity and new quality productivity in China from 2012 to 2022. The empirical results indicate that both industrial agglomeration and new quality productivity indeed significantly promote the growth of export technological complexity, and there exists a pronounced synergistic effect between the two.