High-quality development is essential for China's modernization. The in-depth implementation of the new development philosophy has become crucial for promoting China's development in the context of “domestic and international” double-cycle development. This study constructs an evaluation index based on the new development philosophy, measures the level of China's high-quality development majorly from 2005 to 2020, dynamically examines the spatial and temporal pattern of China's high-quality development on a multi-level spatial scale, and explores its influence mechanism with the help of the obstacle degree model. The results show that: (1) China's high-quality development level has increased as a whole, with the high-quality development index rising from 0.056 in 2005 to 0.092 in 2020, with an average annual growth rate of 3.36% and an overall development pattern of “high level in the east and fast growth rate in the west”. (2) Spatial correlation, China's high-quality development shows a significant positive correlation, with cities with higher levels of high-quality development concentrated in the eastern coastal region, the Pearl River Delta region, and the Beijing-Tianjin-Hebei region, and those with lower levels of high-quality development clustered in the western region. (3) In terms of dynamic evolution, China's high-quality development level shows a small rightward shift, the polarization of high-quality development level is weakening, and the rightward trailing situation has been alleviated. (4) Obstacles to identifying the factors affecting China's high-quality development include the amount of imports, exports, and the number of foreign direct investment contract projects. From the criterion level, openness and innovation are the biggest obstacles to high-quality development, and the obstacle degree of each criterion level shows significant spatial differentiation characteristics in the research period. The results can provide a scientific basis for China's path to upgrading and building a modern socialist country.