yoghurt fortification with nutritional and health valuable mushroom, in relation to its numerous attributes beyond its probiotic benefits was the aim of the studied. Yoghurt milk was supplemented with Agaricus bisporus at levels 0%, 5% and 10%. Thereafter, milk was inoculated with starter cultures, YC containing Streptococcus themophilus and Lactobacillus delbrueckii ssp. bulgaricus, YL containing Streptococcus themophilus, Lactobacillus delbrueckii ssp. bulgaricus, and Lb. acidophilus, YB containing Streptococcus themophilus, Lactobacillus delbrueckii ssp. bulgaricus and Bifidobacterium sp., and incubated at 42oC for complete coagulation (about 3 hr). There after, samples were kept at the refrigerator temperature (5±1°C) for 3 weeks. The obtained results indicated that, yoghurt fortified with mushroom was significantly distinguished with increased values of protein, ash, fiber, pH, curd tension, viscosity, amino acids, vitamins (riboflavin, niacin, B12, biotin, B1 and folate), minerals (Mg, K, Fe, Zn, P, Cu, Mn), organoleptic properiets and daily nutritional values (%). Also the total counts of Str. themophilus, Lb. delbrueckii ssp. bulgaricus, Lb. acidophilus, Bifidobacterium sp. were increased. While the values of fat, cholesterol, titratable acidity (T.A.%), Na and Ca were decreased. The best fortification level with mushroom was 10% and the best bacterial starter culture was Bifidobacterium bifidum. Prolonging cold storage period of all samples was associated with increasing values of T.A., curd tension and viscosity.Finally, it was concluded that, yoghurt beyond its ability to be probiotic food via its culturing with the gut strains, it could further carry more healthy benefits when it was fortified with mushroom at any level up to 10%, but concerning bacteriological and organoleptic properties the level of 5% was preferable.