Increasing consumer concerns on dairy product nutritional quality have stressed the importance of some features of milk such as the fatty acid (FA) profile. In this study, genetic parameters of milk FA profile of dairy sheep are investigated to evaluate the feasibility of breeding for improving the nutritional quality of sheep milk. Individual milk samples of 989 Sarda ewes farmed in 47 flocks located in the 4 provinces of the Island of Sardinia, Italy, were analyzed for FA composition by gas-chromatography. Genetic parameters of 15 FA (expressed as g/100 g of FA methyl ester) were estimated with an animal model, including fixed effects of lambing type, lambing month, altitude of flock, lactation stage, province and parity, and the random effects of flock-test date (FTD), and animal additive genetic. A generally high contribution of FTD to the phenotypic variance was observed (on average 51%). Heritability (h²) estimates ranged from 0.03 for C18:3 n-3 to 0.48 for C16:0. Saturated and unsaturated C18 FA showed moderate to low values of h² (from 0.22 to 0.03, for the same FA). On the other hand they exhibited a large contribution of FTD, ranging from 0.46 for C18:0 to 0.82 for C18:3 n-3, respectively.The high heritability estimate of C16:0 reflects the probable genetic control of its milk content, being partly synthesized de novo in mammary gland. Genetic correlations were negative among C4:0 and short and medium chain SFA. C16:0 showed a negative correlation with most of the investigated FA, and a positive correlation with C4:0, C14:0, C14:0c9 and C16:1c9. The high heritability of C16:0, considered harmful for human health, and its negative genetic correlations with unsaturated C18 FA could be used in genetic strategies to improve the nutritional properties of milk.