Abstract: Based on the essential connotation of high-quality development, this paper constructs an indicator system for measuring the level of high-quality development of the county economy in Guangdong, comprehensively uses the improved AHP method and entropy method model to measure the level of high-quality development of the economy of 57 counties in Guangdong, and explores the spatio-temporal evolution pattern, regional gap sources and distribution dynamics of the level of high-quality development. The research showed that, the score of high-quality development of Guangdong county economy showed a steady upward trend, and the growth of economic aggregate and the increase of per capita stock were the key forces to promote the high-quality development of Guangdong county economy; The spatial distribution of high-quality development level in the county was unbalanced, showing a spatial pattern of “strong core, suitable for the east and west, and weak in the north” ; The regional gap had a trend of gradual expansion, and the overall gap mainly came from the inter regional gap. In the future, it is necessary to realize the steady improvement of the high-quality development level of county economy in Guangdong from the aspects of industrial structure adjustment and optimization, characteristic industry differentiation and cluster reconstruction, “industry-city-people” coordinated development, and inter regional borrowing and cooperation to promote the inter regional linkage development of county economy.