An aerobic digestion of biomass wastes could have a huge impact on renewable energy requirement. Moreover, it reduces biomass wastes and greenhouse gases gas emission. To improve the performance of anaerobic digesters, the co-digestion of different biomass wastes, such as waste activated sludge microalgae, and agriculture wastes including straw dust, wheat straw, rice straw has been performed in this study. The results should that sludge and micro algae have C/N ratio meanwhile, the addition of agriculture wastes to sludge and microalgae mixture increased C/N ratio and improved biogas yield by 197%, 209%, 265% in the cases of adding straw dust, rice straw, wheat straw respectively. Co-digestion with wheat straw show the highest values of C/N for the field stock(20,6) and biogas production moreover, it recorded the highest reduction values for total solids(48.1%), volatile solids (58.3%) and COD(77.5%) as compared to the other wastes