Uncertainties of traditional osteological methods in biological sex estimation can now be overcome with genomic and proteomic analyses. The combination of the three methodologies has been used for a better understanding of gender-related funerary rituals of the Iberian megalithic cemetery of Panoría. As a result, 44 individuals have been sexed including, for the first time, non-adults. Contrary to the male bias found in many Iberian and European megalithic monuments, the Panoría population shows a clear sex ratio imbalance in favour of females, with twice as many females as males. Furthermore, this imbalance is found regardless of the criterion considered: sex ratio by tomb, chronological period, method of sex estimation or age group. Biological relatedness and kinship have been explored as cultural explanations for this female-related bias. The results obtained for Panoría are indicative of a female-centred social structure, in which sex and/or gender would have influenced funerary rites and cultural traditions.