Nine metric parameters were taken on 16 mandibles from adult horses belonging to the Cavall Pirinenc Català breed. Based on these parameters, we develop a descriptive and normality statistics and we obtain correlation coefficients for all the parameters. Thereafter we apply the Kaiser-Meyer-Olkin and Bartlett"s tests and we carry out a Principal Component Analysis (PCA). The PCA selection as the extraction method turns out to be the right one. The use of 8 metric parameters involves a minimal loss of information, and it is possible to exclude the parameter"maximum mandibular length". The parameters related with the branch and angular section appear sensibly differentiated from the rest. The diastem length and the angular section are the more discriminant parameters