To develop biochar for soil conditioner using water plants, characteristics of nutrients release of biochars were investigated under different water plants, manufacturing times and manufacturing temperatures. Under different water plants for manufacturing biochar, the concentrations of T-N and in the water with biochars were higher in the order of CRXDM > ZIZLA > PHRCO > TYHOR > MISSA. The concentrations of in the water were in the order of TYHOR CRXDM > ZIZLA > PHRCO > MISSA. Under different manufacturing times for biochar, the concentrations of T-N, and in the water with biochars were higher in the order of 2 hr > 30 min 1 hr. The concentrations of T-N, and in the water with biochars were on the order of > > under different manufacturing temperatures. Total amounts of T-N and releases in the water with biochars were higher in the order of CRXDM > ZIZLA > PHRCO > TYHOR > MISSA. Using biochars by water plants, total amounts of releases in the water with biochars were on the order of CRXDM > ZIZLA > MISSA >PHRCO > TYHOR. The results of this study suggest that biochars by water plants can supply some of the nutrient requirements of crops and can be a valuable fertilizer.