[Objective] Measures of national key soil and water conservation projects (NKSWCP) were systematically evaluated to provide a basis for improving the quality and efficiency of soil and water loss control in the black soil area of Northeast China, and to promote the high quality development of black soil protection and soil and water conservation. [Methods] The NKSWCP implemented in the black soil region of Northeast China before 2019 was taken as the object, and the slope treatment projects in 52 small watersheds and gully treatment projects in eight project areas were investigated, for which 325 slope map spots and 32 gullies were sampled, respectively. Results were analyzed and diagnosed. [Results] The preservation of gully treatment measures was significantly better than the preservation of slope treatment measures, and the average preservation rates were 95.00% and 56.51%, respectively. There were obvious category differences and spatial differences in the preservation rate of slope treatment measures, while gully treatment measures were generally well preserved, and the preservation rate of ecological land-saving measures was high. A few measures regarding slope and gully treatments are needed to improve construction quality and to strengthen future management in some areas. [Conclusion] In the future, in black soil region of Northeastern China, people should strengthen the optimization and management of traditional measures such as terraces, ridge tillage, and ridge plant belts; develop new ecological land-saving erosion control measures suitable for modern agriculture; and explore the construction of pilot bases for black soil land and water conservation technology. Regular evaluation of the effectiveness of NKSWCP should be conducted, a recommended directory of zoning and classification measures should be put forward, and different types of demonstration samples should be created.