Recently, utilization of biomass (i.e. domestic waste, excess sludge, food processing waste, etc.) is getting an attention as a promising way to realize economical low-carbon society goal. This paper provides a summary of current trends in biomass utilization regarding methane fermentation and sludge recycling technology. Methane fermentation is the process involved the conversion of organic waste to methane gas, which is being used for electricity generation and as fuel. As a plentiful of excess sludge is generated from sewage and night soil treatment plants daily, the recycle technology for biomass utilization is developed. For example; excess sludge and night soil are efficiently dewatered by shaft sliding screw press (to achieve 70% or lower moisture content) and utilized as a combustion improver. In addition, phosphorus in the thickening filtrate generated from the dewatering system is recovered through phosphorus recovery system and utilized as an agricultural fertilizer.