The genetic structure and relationships of five populations of the Iberian group of Iberolacerta (sensuArribas 1999) were analysed by protein electrophoresis. In this study we confirmed the differentiation between the group of populations from Galicia/Cantabrian/S. Estrela versus the group of populations from de Spanish Central System, Gredos and Guadarrama that are included in the two different species by Arribas (Herpetozoa 9(1/2), 31–56, 1996; Russian J. Herpetol. 6, 1–22, 1999), Iberolacerta (I.) monticola and Iberolacerta (I.) cyreni, respectively. However, the differentiation level is not high enough to clearly prove their specific discrimination. On the other hand, we did not confirm the subspecific discrimination of the Gredos –Iberolacerta (I.) cyreni castiliana, and Guadarrama –Iberolacerta (I.) cyreni cyreni populations, proposed by Arribas (1996). These two populations are genetically almost homogeneous. Interestingly, we found an unexpected high genetic similarity between the Galician and the Serra da Estrela populations, presently included into two different subspecies, Iberolacerta (I.) monticola cantabrica and Iberolacerta (I.) monticola monticola, respectively. Their genetic similarity is even higher than that between the populations of Galicia and the Cantabrian Mountains, which are both included in the same subspecies, cantabrica. This result suggests that the populations of Galicia and Serra da Estrela would have maintained contacts, possibly through the north of Portugal, until relatively recent times. Their separation is thus probably post‐glacial. Some evidence also points to the existence of relatively recent contacts between the population of Serra da Estrela and those of the Central System, particularly, with the neighbouring Peña de Francia population. With the cautions imposed by the reduced sample size of our analysis, the significant differentiation of the populations from Galicia and the Cantabrian Mountains allow us to suggest that this last population may not be the result of a recent expansion of the Galician population as Arribas (1996) suggests, but, more likely, the result of a fragmentation process of a more ancient and wider north‐eastern distribution area of this group of rock‐lizards.