The dry anaerobic fermentation plays an important role in the field of bioengineering, especially in the production of energy (biogas) and organic fertilizer. Meanwhile the pollution effect of the solid wastes are decreased. Dry anaerobic fermentations of different organic solid wastes were studied. These included cotton stalks, treated cotton stalks, corn stalks, rice straw, and water hyacinth. The effect of the initial solid concentration, temperature, starter, and buffer additives on dry anaerobic fermentation on biogas production rate and yield has been studied.