The intelligent transformation, digital transformation and network connection of the manufacturing industry (referred to as IDN) is the main way to promote the new qualitative change of the real economy and achieve high-quality development, and the focus is to improve the innovation supply capacity of the key technologies of IND in the manufacturing industry. As the manufacturing industry concentrated distribution area and the forefront of transformation development, the IDN key technology innovation supply capacity of manufacturing industry in Yangtze River Delta has an important leading role and demonstration significance. On the basis of defining the manufacturing industry IDN key technologies and their functional composition, using the national industrial and commercial enterprise registration information and patent information to measure and evaluate the innovation supply capacity of the IDN key technologies of the manufacturing industry in the Yangtze River Delta, which is in the forefront of the whole country and Jiangsu Province is the most outstanding. Finally, in order to further enhance the innovation supply capacity of manufacturing IDN key technologies in the Yangtze River Delta, several policy measures are designed. These measures may help the Yangtze River Delta Economic Zone generate both the demonstration effect and the radiation effect, and drive the high-quality deep integration of manufacturing industry and digital economy across the country in the digital era.