Five strains of probiotic; Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus plantarum, Leuconostoc mesenteroides, and Bifidobacteriwn longum were targeted for enhancing B-group vitamins and fructo-oligosaccharides (FOS) and raffinose family oligosaccharides (RFO) of cashew apple juice (CM) that is an underutilized byproduct from cashew nut processing. Although fermentation by Lb. acidophilus and Lb. casei resulted in increasing B-group vitamins contents (19.25% and 23.11%, respectively) than fermented CAJ with others pro biotic, vitamin B2 levels of fermented CAJ were not different significantly. Results also indicated total sugar contents of fructose, glucose, galactose, sucrose, melibiose, and maltotriose were decreased during 48 h of fermentation. The CM fermented with Lb. acidophilus and Lb. plantation had higher oligosaccharide contents (RFO and FOS). The CM fermented with Lb. acidophilus had the highest FOS of 1-kestose (GF(2)), nystose (GF(3)) and 1F-beta-fructofuranosyl nystose (GF(4)), whereas fermented with Lb. plantarum had the highest RFO (raffinose and stachyose). These results suggest that fermented CAJ could serve as a new prebiotic source with B-group vitamins for functional foods and nutraceutical applications for further human health application.