The mixed ownership reform of state-owned enterprises is an effective way to enhance enterprise innovation and the influence of state-owned economy. Under the background of mixed reform of state-owned enterprises, the data of listed state-owned enterprises between 2003 and 2020 were analyzed, and a vector autoregressive (VAR) model between R&D investment intensity, enterprise performance, degree of mixed reform of state-owned enterprises and government transparency was established, and ADF unit root test, cointegration relationship analysis, AR characteristic root test, pulse division response, and variance analysis were carried out. The results show that there is a positive impact on the innovation performance of enterprises.There is a mediating effect between the degree of mixed reform of state-owned enterprises and the innovation performance of enterprises. From an external perspective, government transparency has a promoting effect on the degree of mixed reform of state-owned enterprises and the intensity of R&D investment of enterprises.