Smut fungi are a large group of biotrophic plant pathogens that cause disease in cereal crops and grasses. Smut fungi often target specific organs instead of infecting the whole plant. They mainly infect the reproductive system of host plants and produce disease symptoms on floral parts or inflorescences. Among all smut fungi investigated and reported, Ustilago contributes a major part with the highest number of species. It has been reported to cause two distinct types of smuts in various crop plants: loose smut in barley and wheat, and covered smut in oats, barley and wheat. Furthermore, the Ustilago causes a corn smut and whip smut of sugarcane. The dimorphic life cycle of Ustilago spp. with dikaryotic filamentous structure is directly linked to the plant pathogenesis. The establishment of a biotrophic, compatible interaction with plants by secretion of specialized fungal proteins effectors. In the present article, the smut fungus Ustilago spp. was discussed with insights into the host range, symptoms, pathogenesis, transmission, epidemiology, and control measures with recent advancements and importance.