DNA flow cytometry (FCM) was performed on archived material of 82 basal cell carcinomas (BCC), using Hedley’s technique. Sixty-five samples were analysed. Biopsy samples were classified in five groups depending on their morphological differentiation: solid, cystic, adenoid, keratotic andmetatypical. Two parameters were studied: proliferative index and DNA index. Statistical analysis revealed that BCC with keratinizing or metatypical differentiation had a greater amount of aneuploidy when compared with BCC without particular differentiation (solid and cystic) or aneuploid differentiation (p < 0.001). The proliferative indices were significantly different in the four groups. DNA FCM of BCC confirms the value of morphological classifications and gives another example of aneuploidy in a tumour with low aggressivenes