Abstract: The IMF is one of three mainstays of postwar international economic order, its functions mainly include:Exercising surveil lance of exchange rate , providing temporary financial as sistance and promoting international economic cooperation.Though the IMF plays an important role in the international financial mechanism, with the development of economic inte gration and financial globalization, it has to be reformed . The thinking of reform of the IMF is discussed from strengthening the status and effect of developing countries in IMF , establishing pre-warning mechanism of financial situation , establishing reserves and improving the supervision of the international capital flows.

Key words: IMF, function, surveil lance