To reveal the development mechanism and current situation of the domestic big cycle, and to conduct research on the construction of the new development pattern and the unimpeded domestic big cycle. Research Methods: Based on the input-output model, the value chain cycle decomposition method is used to measure the level of China"s domestic economic circulation, and the measurement results are -further empirically analyzed by Kernel Kernel density estimation, Thiel index, and improved deviation share method, so as to reveal the current situation and trend of inter-regional and inter-industry circulation in China. Research Findings: The added value of various industries in China mainly depends on domestic circulation. The proportion of domestic inter regional circulation is much higher than that of domestic inter industry circulation. The level of circulation outside the province is also slightly higher than that inside the province. There is a certain spatial correlation and regional difference in the domestic big cycle. The provinces with higher level are mainly distributed in the coastal and riverside economic belts. The development of China"s domestic big cycle shows a downward trend on the whole, and the results of the Theil index show that the difference of the domestic big cycle in various regions (provinces) is gradually increasing. Building a unified national market can effectively curb the difference in the domestic circulation level of each province and improve the overall domestic circulation level. The role path is to improve the regional circulation level by eliminating the blockages in the four links of production, distribution, circulation and consumption. Research innovations: Based on China"s provincial input-output table, this paper comprehensively measures and analyzes the level of domestic circulation, and further divides it into inter-regional circulation and inter-industry circulation, and explores the spatio-temporal evolution trend, regional differences and structural differences of domestic circulation. Research value: It is helpful to understand the current situation and trend of the domestic great circulation from a quantitative perspective, and it is of great significance to smooth the domestic great circulation and build a new development pattern.