Abstract: Background and Objective: Coconut flour is known to be highly nutritious flour and contains high dietary fiber. The aim of this study was to make "bio-yoghurt beverage grafted with coconut flour and containing probiotic bacteria which is recommended as a functional milk product. Materials and Methods: Chemical, phytochemical studies and antimicrobial activity have been performed on coconut flour which was used to make the beverage. Bio-yoghurt beverages made with different ratios of coconut flour (0, 2, 4 and 6%) were chemical, microbiological and sensory tested when fresh and during storage for 15 days of cold storage. Results: Chemical composition of coconut flour showed reasonable contents of moisture, ash, fat, fatty acids, protein, crude fiber, total solids, total phenols and antioxidants. Coconut flour showed antibacterial activity against some foodborne pathogenic bacteria. The addition of coconut flour to make bio-yoghurt beverages increased its contents of total solids, protein, ash, fiber, acidity, antioxidant activity, total phenols, improved yoghurt sensory and rheological properties especially when probiotic bacteria were used. The results did not reveal any significant differences (p>0.05), between the bacterial counts of yoghurt starter culture, Lactobacillus rhamnosus, Lactobacillus casei in yoghurt control (without coconut) and bio-yoghurt treatments (with coconut), during cold storage. Moulds and yeasts were not detected in all bio-yoghurt treatments; meanwhile they appeared in yoghurt control after 15 days indicating coconut antifungal activity and subsequently a period of time to save more for this drink. All bio-yoghurt beverages with different ratios of coconut flour were sensory accepted and showed more favorable properties, particularly for the viscosity. Conclusion: A new functional dairy product of bio-yoghurt beverage contain coconut flour high fiber content was prepared with probiotic bacteria and showed good chemical, microbiological and sensory/rheological properties.