The Yangtze River Delta is one of the regions with the most active economic development，the highest degree of openness and the strongest innovation ability in China，and plays an important role in the national economy. In recent years，under the trend of a new round of scientific and technological revolution and industrial reform，all provinces and cities in the Yangtze River Delta take the development of digital economy as an important engine to promote industrial upgrading and regional development. Therefore，it is of great significance to analyze and study the development of digital economy in Yangtze River Delta. This paper comprehensively combs the development of digital economy in Yangtze River Delta and other provinces and cities from the aspects of scale growth，policy documents，industrial layout，park layout and key cities，so as to provide useful reference for future development practice.