The present work concerns the study of the nutritional quality of the raw milk, on samples resulting from centers of collection of the milk (cooperatives) and from farms, from the region of Tadla (Kssiba and Fkih ben Saleh) and the region of Kelaa. The investigations concerned two periods of year 2011 (Period I: February-March-April and Period II: September-October-November). The analysis results show that for the three nutritional parameters, protein content (TP), fat (MG) and defatted dry matter (ESD), there are variations between samples. Assessing the nutritional quality of milk is required to highlight the variability in the nutritional quality of milk production, evaluating the quality of milk produced in those regions and determine the factors influential to improve production and profitability. This quality is demonstrated through the determination of three main parameters of milk constituents, namely fat (MG) Protein content (TP) and nonfat dry (ESD). Milk quality plays an important role in marketing milk and quantity of product plays a very important role to meet the demand of the market in terms of milk and its derivatives. The effect of time and the origin of milk (cooperative or farm) are the two parameters that influence in a significant way the nutritional quality of milk. The results of exploratory analysis by applying the principal component analysis (PCA), illustrates the importance of these two parameters.