Te aim of the work was to reduce the presence of the potentially atherogenic fatty acids (FA) of milk (C12: 0,C14: 0 and C16: 0) and increase the presence of conjugated linoleic acid (CLA) in confned dairy cows fed a total mixed ration (TMR) supplemented with polyunsaturated fatty acids (PUFA). Two batches of 70 multiparous cows in the frst third of lactation were used. Afer six experimental weeks and for fve consecutive days, milk samples (5) were obtained from the collector tank of non-supplemented cows (LE) and of CLA milk (LCLA) from the tank of PUFA supplemented cows. Fat content (g/100g) in LE (3,84) was higher (p<0,001) than LCLA (2.84) explained by a signifcant reduction (17,21%) in the concentration of the potentially atherogenic FA of milk. The milk atherogenic index was higher (p<0,001) in LE (4,07) compared to LCLA (2.58). Milk CLA content increased (p<0,001) by 122% in LCLA (0,77 g/100 g FA) compared to LE (0,34 g/100 g FA). Oleic acid concentration (g/100 g FA) resulted higher (p<0,001) in LCLA (23,37) compared to LE (18,78). Supplementation with PUFA in confned dairy cows increased the healthy value of the milk produced maintaining an adequate omega-6/omega-3 ratio (6,59) and confrmed the plasticity in milk fatty acid composition.