Abstract: The connotation and development mode of intelligent manufacturing are studied. By adopting the descriptive case study and taking the intelligent manufacturing development of Sany Group as an example, the development mode at various stages and the construction of the Internet of Things platform have been studied and analyzed comparatively. The intelligent manufacturing transformation process of Sany Group is summarized as three stages, including product intelligence, manufacturing intelligence and service intelligence. Based on this, some enlightenments are put forward for Chinese manufacturing enterprises to carry out intelligent manufacturing transformation and develop industrial Internet of things.