Functional   yoghurt drinks  ( Y.D )  were prepared  as follows : treatment A ( Y.D. + 3% oat + 6% sucrose ) , treatment B ( Y.D. + 3% oat +0.25 % stevia ) , treatment C ( Y.D. + 6% sucrose , control ) .All drinks were stored at 5 ± 1 °C for 15 days and analyzed for  chemical ,  microbiological , rheological , and sensory  properties . Total energy , total solids ( T.S ) , fat , total protein , carbohydrate and ash contents were found highest in treatment  A , during storage period .Treatment A recorded the highest values of viscosity  and the lowest rate of whey separation . Total dietary fibers was found higher in fresh  treatment B . Seven essential amino acids  ( EAA) and ten  Non-essential amino acids ( NEAA ) were detected in all  fresh Y.D samples . Valine  amino  acid  was the predominant amino acid in EAA and Glutamic acid  was the corresponding one in NEAA. Sulfur  amino  acids  ( Methionine & cysteine )  were also detected in all  treatments. The ratio between EAA  :  NEAA  was  found  highest  in Y.D  A  , followed by  B   and C , in order . Counts  of lactic acid bacteria  in yoghurt drinks fortified  with oat  were found the highest . Yeasts & Molds were  appeared in  low  counts  in  all  treatments  at  the  day  15 of storage . Therefore ,  low calorie functional Y.D. sweetened with stevia and fortified with oat powder  may be produced successfully