Whey is a by-product of cheese processing. Yet, it still contains nutrition from milk. Thereby, it still can be further processed into another product, such as a whey probiotic drink. This research aimed to obtain probiotic starter and best skim concentration as study their interaction to produce a whey probiotic drink with the quality properties and is sensorically acceptable. The present study used completely randomized design with two factors i.e. type of probiotic starters (Lactobacillus casei and Bifidobacterium longum, and combination of both) and skim milk concentration (5%, 10%, and 15%). Analyzes were performed on pH, total acid, protein, viscosity and total of probiotic bacteria. From nine of treatment combination, four among them were selected to be analyzed for their sensory acceptability. Research yielded a whey probiotic drink using starters of Lactobacillus casei and Bifidobacterium longum with the concentration of skim milk was 15%, pH 3.82, total acid 1.18%, viscosity 53.4 cP, protein 3.24% and total probiotic bacteria 8.18 x 109 CFU/mL. The product had also good overall acceptability.