Abstract: Bioenergy, a renewable energy holds a promising solution to the most pressing problems of energy crises and waste treatment, disposal and thereby creating a circular economy. There is a need to exploit biogas potential to the fullest to enhance its productivity and utilize it for heating, cooling, generating electricity and also for transportation. Valorisation of the municipal solid waste (MSW), agricultural non-fodder waste, sewage sludge, animal waste, etc., for energy production (biogas), material recovery (fertilizers) and waste elimination (waste treatment) attracts the attention of the researchers. This research review highlights the crucial parameters like pH, temperature, OLR, HRT, etc. affecting the biogas productivity and provide insights to run the digesters at optimum conditions thus optimizing the biogas yield. Keywords: Biogas, Bio-energy, Anaerobic Digestion, Co-digestion