The private economy is an important guarantee for the stable economic and social development of the three northeastern provinces. In the first half of 2021，the private economy of the three northeastern provinces showed a good development trend，with the characteristics of continuous growth in the overall scale of operation，the emergence of specialized and special new enterprises，the continuous optimization of the business environment，and the continuous enhancement of financial service capabilities. But the same time，through the operation data of the first half of 2021，it can also be found that there are still outstanding problems，such as low overall level、poor financing channels and weak innovation capabilities in the development of the private economy in the three northeastern provinces. In order to ensure the rapid recovery and healthy development of the economy enterprises，the three northeastern provinces should promote the high quality development of the private economy in the three northeastern provinces by continuously optimizing the business environment and stimulating the vitality of innovation.