The world is facing severe problems of energy crisis and environmental problem. This situation makes people to focus their attention on sustainable energy resources for their survival. Biomass is recognized to be the major potential source for energy production. There are ranges of biomass utilization technologies that produce useful energy from biomass. Gasiﬁcation is one of the important techniques out of direct combustion, anaerobic digestion – Biogas, ethanol production. Gasiﬁcation enables conversion of these materials into combustible gas (producer gas), mechanical and electrical power, synthetic fuels, and chemical. The gasiﬁcation of biomass into useful fuel enhances its potential as a renewable energy resource. This paper gives a comprehensive review of the techniques used for utilizing biomass, experimental investigation on biomass fuels, characterization, merits, demerits and challenges faced by biomass fuels.