Ecological security pattern is important for alleviating contradiction between the ecological protection and economic development. In this paper, we chose Northeast China as the research object and comprehensively referred to Technical Guideline for Demarcating the Red Line of Ecological Protection, National Ecological Function Division, and the level of natural resources and socio-economic development. Firstly, the ecological sources were divided based on the functional and sensitive indicators of water conservation, windbreak and sand fixation, biodiversity maintenance and protection. Then the basic ecological resistance surface was modified by night light data, and minimum cumulative resistance (MCR) model was used to divide buffer zones, identify ecological corridors and strategic nodes, so as to construct the ecological security pattern in Northeast China. The results showed that the ecological source area of Northeast China was 650000 km², accounting for 45.02% of the whole region. The area included 18 ecological sources, which mainly distributed in Daxing'anling Mountains, Xiaoxing'anling Mountains, Changbai Mountains, and part of the western grassland. Based on MCR model, we divided high, middle, and low buffer zones. The total length of the central line of the key ecological corridors was 11073.52 km and 29 ecological strategic nodes were identified. And all these formed a network spatial layout between ecological sources in Northeast China. We expected the results could provide some scientific reference for the regional ecosystem services and the formulation of sustainable development policies.