Cow dung in Kadipaten Village of Kedungjambal, Tawangsari, Sukoharjo had not been managed appropriately. Actually, the organic substance contained in cow dung is potentially used as raw material for biogas making. To accelerate the time needed in the biogas processing, biostarter can be added such as pineapple peels waste. The aim of the study was to identify which biostarter concentration is t…