Moroccan economic authorities adopted the devaluation of the dirham, during the adjustment period, as a measure of economic regulation for the first time in the monetary history of Morocco, officially and excessive rate of 9%. The dirham is considered overvalued by international experts, plus the commercial slump has pushed for the adoption of this instrument as a means of economic adjustment. But action by the exchange rate required an adjustment of the direct and indirect dirham. Certainly, one cannot deny the virtues of devaluation and say that it has a total failure. Indeed, the descriptive study of official data from the Moroccan economic authorities reflects the recovery ensured at certain levels by means of managing the exchange rate. But it is accepted that the first direct effect of the exchange rate is that the commercial account. Our goal in this analysis is to assess the impact of devaluation on this account by measuring the extent of absorption of the trade deficit. To this end, we will use indicators on the terms of exchange rates and other indicators on competitiveness. The evaluation will be among others an audit of three expected effects of devaluation: The effect price; The quantity effect; The structure effect.