This paper takes the economic development of counties in Henan Province as its research object, using data from 82 county-level regions in Henan Province from 2011 to 2020 as its sample. From five dimensions—innovative development and transformation of growth drivers, coordinated development and structural optimization, green development and low-carbon actions, open development and efficiency reforms, and shared development and urban-rural coordination—a comprehensive evaluation index system for high-quality county-level economic development is proposed, comprising 21 tertiary indicators. The weights of each indicator are determined using the entropy weight method. Based on the established evaluation index system, the overall development trends of the research subjects from 2011 to 2020 were analyzed using PCA clustering analysis, preliminarily dividing the 82 county-level regions in Henan Province into three categories: steady development type, development divergence type, and weak development type. With the level of high-quality county-level economic development as the core explanatory variable and the digital finance development index as the explanatory variable, a multiple statistical regression model was constructed to explore the influence mechanism and threshold effect of the digital finance development index on high-quality county-level economic development. In the robustness test, the regression coefficients of the digital finance development index remained positive, and all three estimation results were significant at the 1% level, indicating that it indeed played a significant promotional role in driving the high-quality development of county-level economies in Henan Province.
