The objective of this experiment was to evaluate the effect of a dietary supplementation of lampant olive oil on the fatty aid profiles of the milk and cheese of ewes. Nine lactating ewes were used in a 3 × 3 Latin square design. Dietary treatments were supplemented with 0 (control; T0), 36 (T1) and 88 (T2) g of lampante olive oil/kg of dry matter intake (DM). DM, milk yield and milk composition (fat and protein) were not affected by dietary treatments. Oleic and vaccenic acids gradually increased (P < 0.05) and the saturated FA and atherogenicity index decreased (P < 0.05) in milk and cheese as the concentration of lampante olive oil was increased in dietary rations. Overall, the supplementation of lampante olive oil in the diets of lactating ewes increased monounsaturated FA and decreased saturated FA concentrations in milk and cheese, thus improving their quality from the human health standpoint.