Struvite is a yellowish white or brownish yellow crystal. Struvite occurs in an alkaline environment. The reaction that occurs is the reduction of H+ and at the anode is H2O oxidation. The purpose of this study was to determine the maximum potential conditions of deposition of struvite which was contained in biogas waste by electrolysis process and to improve the quality of struvite fertilizer. The method was carried out with the electrolysis time condition of 30 minutes where the electrical voltages used were 1V, 3V, 5V, 7V, and 9V and the size of the electrodes used were 30 cm, 36 cm, 50 cm, 60 cm, 70 cm. From the research that has been done, it could be seen that the struvite formed was very small, the best conditions in this study at 5V voltage and 36 cm electrode area with a yield of 28.8%.