Abstract: The effects of different amount of organic fertilizer application in the nuisance-free cultivation technique on quantity and quality of water spinach were studied in the paper. The results showed that under the condition of this experiment, there was an obvious increase on growing situation, earlier growing stage and output when medium organic fertilizer (15000kg/hm2) was applied on the water spinach. But it won’t increase much if excessive organic fertilizer (225000kg/hm2) or insufficiently (7500kg/hm2) is applied. In one growing period, the change of nitrate content had obscure regularity when the different quantity of fertilizer was applied. In the whole growing cycle, the nitrate content in the plant changed from little to more and then to little. But it was lower than the national standard all the while. As to the content of Vc, the change was not obvious.