The rapid growth of population and social economy, accompanied by the sharp change of land use pattern, has resulted in the loss of natural ecosystems and the degradation of ecosystem services, and thus threatened the sustainable development of human society. It is important to identify and protect key ecological areas to maintain the stability and sustainability of the ecosystem. The construction of ecological security pattern is an integrated approach to protect regionally ecological and society economic sustainability. Taking Liaohe River Basin as a case study area, this paper constructed the ecological security pattern of Liaohe River Basin through the following three steps. Firstly, based on the evaluation of the importance of ecosystem services, the ecological sources were identified through quantitative evaluating four ecosystem services, i.e. carbon fixation, soil conservation, crop production, and water yield. Secondly, we built resistance surface by synthesizing above ecosystem services. Finally, we identified the ecological corridors and key nodes by using circuit theory. The results showed that ecological security patterns in the Liaohe River Basin included 129 ecological sources, 243 ecological corridors, and 38 pinch-points. In details, the ecological sources were mainly distributed in the east of Liaohe River Basin, with the ecological corridors extending along the interlaced zone between plain and mountain areas in a shuttle shape, and both ecological sources and corridors were mostly covered with forest land. The "pinch-points" were distributed along the river in the middle of the study area, mainly covered by forest land and cultivated land. Identifying the spatial range of ecological corridors and the specific location of key nodes for effective ecological conservation based on ecosystem services and circuit theory, this paper puts forward a new idea for alleviating the increasingly sharp contradiction between economic development and ecological protection in Liaohe River Basin.