Aureobasidium pullulans, popularly known as black yeast, is one of the most widespread saprophyte fungus associated with wide a range of terrestrial and aquatic habitats, in temperate and tropical environment. It is a polymorphic fungus able to grow in single yeast-like cells or as septate, polykaryotic hyphae showing synchronous conditions, with budding cells. This fungus has been exploited potentially for commercial production of various enzymes (amylase, xylanase, and pectinase etc.), single cell protein, alkaloids and a polysaccharide namely pullulan. In the light of the above facts, this review article has emphasized on the orientation, morphology, biochemical characteristics, habitats and its economic potentials with special reference to pullulan.