The aim of this study was to investigate the differences in the fatty acid composition between the core and the membrane of the fat globules (MFGM) in sheep's milk during lactation.Individual milk samples were collected from seven Massese ewes and analyzed for fatty acids from whole milk, from the core and from the MFGM.The MFGM showed more saturated fatty acids (SFAs) than the core, specifically C16:0 (+21.5%) and C18:0 (+67.64%), and more polyunsaturated fatty acids (PUFAs) (+48.66%). The core had a higher content of monounsaturated (MUFAs) (+12.36%) and short chain fatty acids (SCFAs) (+640.42%).SCFAs showed higher values (P ≤ 0.05) in milk at 60 days of lactation and lower values (P ≤ 0.05) at 30 and 120 days. These changes in the SCFAs occurred mainly in the core, whereas the amount of SCFAs in the MFGM remained almost unchanged.The medium chain fatty acids increased with advancing lactation in the whole milk, in the core and in the MFGM; the long chain fatty acids on the other hand decreased.In addition, the SFAs increased during lactation, while MUFAs and PUFAs tended to decrease in the decreasing lactation phase; the same trends were observed the core and in the MFGM.