Abstract: Results of long．term fertilization trial showed that application of organic manure alone increased soil fertility．the increase of biomass was not much，but economic yield was much higher than that iqcontro1．The improvement of yield was limited without nitrogen fertilizer application．Over several years’
cultivation with organic manure and nitrogen fertilizer potassium amount in soil turned out insufficient，therefore there was an apparent increase of yield with combined application of potassium and nitrogen．There was almost no effect for yield improvement with application of phosphorus．Extra phosphorus application resulted in less yields under suficient phosphorus condition．On the base of observation and analysis of our long-term fertilization trial，“the regular of one third capacity of nutrient-yield” and effective standard for nitrogen，phosphorus and potassium application were put forward． Nutrients were used economically when soil fertility or yield WaS quite high．There was a range for parameters of fertilizer requirement，SO it should be adjusted according to soil fertility and yield．

Key words: Long-term fertilization trial, Vegetable cultivation, Biomass, Economic yield, Nutrient absorption amount, Fertilizer requirement