Abstract: The responses and optimum application rate of NPK fertilizer for the Chinese cabbage were studied by conducting field experiments.The results showed that the average contribution rate of soil fertility to the Chinese cabbage productivity was 47.4%.The Chinese cabbages that received N,P and K increased their yields by 41.26%,14.90% and 25.53%,respectively,on the average.In other words,the effectiveness on productivity improvement was N>K>P.The output/input ratios on N,P and K were 13.8,13.2 and 9.7,respectively.N fertilizer had a higher output/input ratio than P or K fertilization when the soil fertility was low.On the other hand,the P and K had higher output/input than N in the soil of high fertility.The recommended application rates of NPK for the Chinese cabbages were found to be N 232.0 kg·hm^-2,P₂O₅70.5 kg·hm^-2 and K₂O 209.6 kg·hm^-2,or 1:0.3:0.9 in proportion.The predicted output was 33308.7 kg·hm^-2.

Key words: Chinese cabbage, soil, NPK, fertilizer response, optimum application rate