Abstract: Agricultural modernization is a key part of the coordinated development of the "five modernizations". The improvement of its level is conducive to complementing the shortcomings in the evolution of modernization and promoting a unified development pace. In order to analyze the development status of regional agricultural modernization in-depth, the article builds the evaluation index system of agricultural modernization development level. Using the entropy weight TOPSIS method, the modern agricultural construction level of Heilongjiang, Jilin and Liaoning is estimated from 2014 to 2018, and its dynamic factors and characteristics of spatial and temporal evolution are explored. The research results show that: Among the evaluation indicators, the weight of economic crops in the total sown area and the effective irrigation area of farmland have greater weight and increased fluctuation in impact; in the evaluation score, the level of agricultural modernization in Liaoning Province is significantly better than the other two Province, the development level is relatively high, while Heilongjiang Province is closely followed, and the development level of Jilin Province is relatively weak. Combining the evaluation index weights and the evaluation results of Northeast China, the countermeasures for modern agricultural construction, such as improving the level of agricultural technology, ensuring the supply of agricultural funds, adjusting the structure of agricultural production, and strengthening agricultural ecological protection, are proposed. Research can provide a scientific basis for building modern agriculture, enhancing agricultural carrying capacity, and promoting rural revitalization.