This paper focuses on the total volume of Sino - US bilateral trade and comprehensively applies a variety of econometric methods for time - series analysis. By sorting out the Sino - US trade data from 1980 to 2019, covering variables such as the total volume of imports and exports, price indices, and trade barriers, descriptive analysis reveals the growth trend of trade volume and the nodes of fluctuations. Unit root tests are carried out to make the data stationary, Granger causality tests are used to determine the causal relationships between variables, and cointegration tests find 3 cointegration equations. Furthermore, a least - squares regression equation is constructed. Impulse response analysis shows that the growth rate index of the total volume of Sino - US trade and the growth index of China's consumer prices have a significant short - term impact on the growth rate index of China's global total volume of imports and exports, but the long - term impact weakens. Variance decomposition indicates that the growth rate index of China's global total volume of imports and exports itself has the greatest impact on it. The research results provide a basis for a deep understanding of the Sino - US bilateral trade relationship and have reference value for the formulation of trade policies and related research.