Meristic counts and morphometric measurements were carried out on fresh sand sole Pegusa lascaris (Risso, 1810) obtained from commercial landings in Iberian waters: Gulf of Cadiz, Algarve (South of Portugal) and Porto (North of Portugal). Three meristic and nine morphometric characters were examined for geographic variation. The Kruskal-Wallis test indicated a significant difference at 5% level of confidence in the meristic counts among the three localities. A principal component analysis was performed to analyse the morphometric variables. The results showed that around 84% of the total variance was explained by the three first components. All variables were highly scored with the first PC, except the pectoral and pre-anal lengths and minimum height (0.797, 0.825 and 0.794, respectively). Linear nested models were used to estimate the allometric relationships between the morphometric variables and to assess sex and geographic effects in the estimated parameters. The F-test used to test the equality of the regression parameters showed, in general, a significant sex and/or geographic effect (p < 0.05), except for the relationship between total length and pectoral length. These results clearly demonstrated geographic variation between the morphometric characters of sand sole in Iberian waters.