Nitrification of human urine performed for its stabilization, and culture of Spirulina platensis in the nitrified human urine were investigated for nutrient recovery. With daily adjusting to pH 8 and keeping high dissolved oxygen concentration, mean 95.0% of NH(4)-N in human urine can be finally stabilized and oxidized to NO(3)-N. Furthermore, this nitrified human urine seems to be an ideal culture medium for S. platensis. Without pH adjustment, only about 50.0% NH(4)-N could be converted, i.e. NH(4)NO(3) would be formed. Under low dissolved oxygen concentration, mainly short nitrification (from NH(4)-N to NO(2)-N) occurred.