Promoting coordinated regional development is a crucial pathway for building a new development paradigm and an inherent requirement for addressing imbalances and inadequacies in development. Based on theories of coordinated regional economic development and high-quality economic growth, this paper constructs an evaluation index system for Shandong Province’s high-quality economic development by integrating the new development philosophy. Combining the entropy weight method with the TOPSIS method, we calculate Shandong’s comprehensive score for high-quality economic development and introduce kernel density estimation to measure the spatial differentiation characteristics of this development. To explore the impact of digital finance on Shandong’s high-quality economic development, a regression model was constructed using the digital inclusive finance index as the explanatory variable, supplemented by empirical analysis of data from 16 cities in Shandong. Findings reveal that from 2011 to 2024, Shandong’s overall level of high-quality economic development increased by 1.25 times, with a notably high average annual growth rate during the study period. The impact of digital finance on Shandong’s high-quality economic development exhibits a significant positive effect at the 1% significance level. Each 1% increase in digital finance correlates with a 0.583 percentage point rise in high-quality economic development levels. Moreover, the influence of digital finance demonstrates significant regional heterogeneity. Therefore, Shandong Province needs to further improve digital financial infrastructure across its cities to promote coordinated regional development and collectively advance the province’s high-quality economic development.