The ecological security index (ESI) system including 27 indices for Heilongjiang Province was built up with the pressure-state-response (P-S-R) model. The weights of the indices were determined by analytical hierarchy process (AHP) and the ecological security status classification was evaluated by the ESI model for the years of 2000-2005. Then the development trend of ecological security from 2006 to 2010 was forecasted with the grey dynamic model. The results showed that the ecological security ranked the V grade in 2000 and the III grade in 2005, indicating the increase of ecological security. The forecasting results show that the ecological security will be the III grade for 2006, the II grade for 2007-2009, and the I grade for 2010 (ideal security). Thus it can be seen that the ecological security is ascending year by year, and the ecological environment quality is obviously improved with the implementation of eco-province construction since 2000. Through the effective facilitation of eco-province construction etc., the sustainable and healthy development of ecological security will be finally realized in Heilongjiang Province.