One of the most important instruments of economic policy of the opened countries is the exchange rate. It is considered both a mean of monetary regulation and a tool of outside competitiveness. Morocco plans to adopt the floating exchange rate regime, in the end of 2009. Indeed, the question which arises today is to know what type of floating exchange rate regime will be applied. Under the economic, technical and institutional factors, we ask if Morocco is ready and able to adopt this regime. In the light of this report, this paper will deal with the impact of the exchange rate policy on the real economy in Morocco through an empirical model called « The Behavioural Equilibrium Exchange Rate » supported by Clark and MacDonald (1997). Firstly, our investigation deals with the efficiency of exchange rate policy adopted by Morocco, secondly, it deals with the capacity of Dirham to resist to the shocks caused by the misalignments and finely, with the Moroccan monetary authorities’ capacity to manage the existing exchange regime. Under using the cointegration method, the error correction model and the analysis of the shocks by using the method of the decomposition of variance, our results confirm that the dynamics of the exchange rate in Morocco is determined by the variables such as the terms of trade, the foreign assets and the foreign debt. Similarly, in terms of short-term fluctuations in the exchange rate and in the analysis of the shocks, the supply and demand dynamics the dirham seems determining.