This study was performed to characterize the ability of active Bifidobacteria strains and Avocado to produce conjugated linoleic acid (CLA).Using Bifidobacteria such as B. breve, B. bifidum and B. lactis showed an increase in CLA that convert linoleic acid (LA) to conjugated linoleic acid (CLA). In first part set yogurt was manufactured using buffalo milk 6% fat, with adding B.breve, B.bifidum and B.lactis. Each of the prepared yoghurt assessed for chemical, microbiological and organoleptic properties when fresh and during refrigerated storage at 6± 1˚C for 14 days. Results indicated that using probiotic bacteria (B.breve, B. bifidum and B. lactis) was effective in producing conjugated linoleic acid (CLA) in yoghurt treatments during fermentation as compared with the control yoghurt. Contents of probiotic bacteria (B.breve, B. bifidum and B. lactis) were decreased in yoghurt treatments during storage, Firmness, Synersiss and pH values were also decreased while T.S, Fat and acidity increased. In second part stirred yoghurt was made using the same Bifidobacteria species and 10% or 15% avocado fruit. Each of the prepared yoghurt was assessed for chemical, microbiological and organoleptic properties when fresh and during refrigerated storage at 6± 1˚C for 14 days. Obtained results indicated that adding avocado fruit to probiotic yoghurt highly increased CLA content in all yoghurt treatments tell the end of storage period. Also Bifidobacteria counts gradually increased during storage period.