Cashew apple, the peduncle of cashew fruit, is an agricultural waste byproduct from harvesting cashew nuts. Cashew apple juice contains about 10% reducing sugar. Its bagasse contains about 20% of cellulose. The byproducts can be used as a substrate for several microbial fermentation processes. Wine and bioethanol were produced by Saccharomyces cerevisiae. Probiotic beverage and lactic acid were produced by Lactobacillus casei. Biosurfactants-rhamnolipids, emulsan and surfactin were synthesized by Pseudomonas aeruginosa, Acinetobacter calcoaceticus and Bacillus subtilis, respectively. Tannase and pectinase were produced during solid-state fermentation of Aspergillus spp. Prebiotic oligosaccharides were synthesized by the activity of dextransucrase produced by Leuconostoc spp. Cashew apple is a potential substrate for producing a variety of products, depending on the type of microorganisms used.