Pretreatment of biomass processes and technologies provides general information on one of the most promising renewable energy sources. The biomass pretreatment can be done using different methods viz physical physicochemical and biological pretreatment each method has its advantages and limitations the efforts are underway. The most promising methods of lignocellulosic biomass pretreatment are hydrothermal treatment and organosolv fractionation as these are the only thermochemical processes with proven commercial . Pretreatment of biomass provides general information basic data and knowledge on one of the most promising renewable energy sources biomass for their pretreatment which is one of the most essential and critical aspects of biomass based processes development the quest to make the environment greener less polluted a