Two populations of roe deer from Spain, approximately 300 km apart from each other and currently recognized as separate subspecies. were studied to analyse the nature of the morphological differences between these populations and to assess the validity of its taxonomic division. Sixty-one skulls of roc deer from the Occidental Cantabric Mountains (OCM) and 17 from the Northern lberic Mountains (NIM) were used. No significant sexual dimorphism allowed pooling of male and female samples, on which a large set of 53 measurements was taken. Skulls from the OCM population are, on average, 1·9% larger than those from the NIM population. Twenty-five out of the 53 characters showed some degree of significant differences between means of both populations, though only four showed highly significant differences. Mandible characters were the most variable traits, showing also significant differences between populations. Eight principal factors were extracted. explaining a total of 84·7% of the sample variance. An ANOVA of factor scores from each population revealed significant differences in PF 1 and PF 3. Interpretation of these two factors suggests that morphological differences between both populations can be summarized as specimens from OCM having larger mandibles and broader neurocranium than specimens from NIM. Mandible differences might reflect morphological adaptations to favour the consumption of ligneous plants, which are more frequently eaten by the OCM roe deer population, whereas a broader neurocranium might be related to antler size. It is concluded that biometric differences observed in skulls from these two populations only reflect minor morphological adaptations to different habitats, thus. there is a lack of morphological data to support the taxonomic distinction of the OCM population as a separate subspecies.