β-Glucans are widely distributed among nature especially in fungus, yeasts, bacteria and cereals cell walls. β-Glucan comprises of D-glucose monomer units linked together via (1→3) β-glycosidic bonds and also they have connected to the side chains by either β (1→6) or β (1→4)-link within different distances. Because of their unique characteristics such as water solubility, viscosity, molecular weight and etc., they widely utilized in various food systems and in medicine also as the human health improvement. Among them, fungal β- glucans have a novel approach, due to anticancer, antitumor, anti-inflammatory and anti-aging properties, which are more considered as one of the most important bioactive compounds. Hence, considering the importance of fungal β-glucan sources in the food industry and medical, this study intends to via review and summarize the available, valid and recent literature, to introduce the structure, synthesis and biological activity of fungal β-glucan and their applications.