According to policy economics, just as the change of any policy instrument should be in conformity with the law of policy, so does the exchange rate movement.On the one hand, adjustments of the RMB exchange rate are estricted its boundary condition, that is, purchasing power parity, so its objective tendency to come is appreciation.On the other hand, RMB should be depreciated since China's future economic targets are determined sufficient employmen t and excited consumption.However, a great appreciation of RMB, as well as its considerable depreciation, is inadvisable.Under such a context the tactful way of the RMB exchange rate fluctuation should be an irregular small appreciation in accordance with J.Tinbergen's model on exchange rate policy, so that China's economic multi-targets can be achieved and the impact of international speculative capitals on China's economy can be resisted.