Abstract: In recent years, there have been repeated emergencies of coal supply in the three Northeast provinces during the heating season, which has become a major regional livelihood issue. It is necessary to find the root cause and respond in many ways. The author sorts out the current coal supply pattern in the three northeastern provinces, and argued that the contradiction between supply and demand and transportation bottleneck during the peak period of winter coal use are the key issues of supply security. The author also analyzes the three major constraints of medium and long-term coal supply, namely the decline of its own production, the long-term existence of transportation bottlenecks during the peak period of winter coal use, and the limited production capacity in eastern Inner Mongolia, and then combined with the consumption of coal to predict that the external dependence of coal in the three northeastern provinces will continue to increase, and the pressure of supply will continue to exist. The countermeasures will be proposed from three aspects: improving coal production capacity in eastern Inner Mongolia, improving railway emergency dispatch capacity, and building some coal reserve distribution bases.