The oppida at Alarcos and El Cerro de las Cabezas (Ciudad Real, Spain) were two of the most important Iberian sites in the Proto-history (8th-3th centuries BC.) the Northern Oretania. Archaeological studies have been published since the 80s; however this paper is the first that provides archaeometric results from the chemical and mineralogical analysis of 107 ceramic fragments of Iberian common pottery. They have been analysed through X-ray diffraction (XRD) and X-ray fluorescence (XRF). From the chemical results, a statistical study has been carried out, which has allowed us to create reference groups (RG) and to determine the economic relationships between the two sites studied and their areas of influence. At a technological level, the results from the mineralogical analysis have allowed us to estimate the firing temperatures (EFT) and to classify the ceramic fragments into 3 fabrics with their respective temperature ranges.