This paper analyzes the political and economic situation of Mongolia before and after the international financial crisis，and studies the Sino-Mongolian cooperation in retrospect and prospect. Although Mongolia maintained relatively fast economic growth before the international financial crisis，some structural risks existed in its developmental pattern and macroeconomic policies. The crisis emerged the risks’ negative effects，which aggravated the political and economic situation of Mongolia. But there were some positive factors should be high priorities. The crisis has further exposed the endogenous vulnerability factors in the economic structure of Mongolia，but also profoundly reflected the needs of each other between China and Mongolia. China and Mongolia should strengthen cooperation to fully expand the inheritance of the crisis on which we have paid a lot.