Abstract: The effects of water-soluble chelated fertilizer with different using patterns on the yields and quality of pakchoi were studied with pot experiment in this study. Results showed that the yields of pakchoi were markedly increased as chelated fertilizer was applied with irrigation. At the same time the dosage of fertilizer application was greatly decreased and the using efficiency of fertilizer was greatly elevated. However, when the concentration of the solution of irrigation was too low, the yields of pakchoi were reduced because of the shortage of fertilizer. The quality of crop could be improved when chelated fertilizer was supplied with irrigation. Compared to common fertilizer, the vitamin C content in the leaf of pakchoi was increased and nitrate content had the highest decreasing amplitude of 51.3% when the chelated fertilizer was applied at the rate of 800mg/kg with irrigation.