Abstract: To improve the research on the security of cultivated land resources in various regions, taking Heilongjiang, a province with concentrated contiguous arable land, as a research area, we constructed a security evaluation index system for cultivated land resources, and quantitatively analyzed the security status and trend of cultivated land in Heilongjiang from 2007 to 2016 by the entropy method, comprehensive evaluation method and obstacle degree model. The results showed that: (1) the security of cultivated land resources in Heilongjiang experienced the“critical safety-safer-critical safety-safer”fluctuations from 2007 to 2016; (2) through the analysis of the criteria layer scores and trends, we found that the ecological security score had a big fluctuation, and the ecological security problem of cultivated land was prominent; (3) after calculating the index data of the research area from 2007 to 2016 with the obstacle degree model, we found that the obstacle degree of the ecological security index factor was more and more prominent in the middle and late period; the problem was concentrated on the excessive input of agricultural chemical production materials. Based on this, it is necessary to control the input of chemical production materials and implement effective crop rotation, fallow system and agricultural production compensation mechanism.