Field experiments of treatments concerning balanced and conventional fertilization, including lack of N or P or K fertilizer, using potassium chloride to replace potassium sulphate were set up. The results showed that the comprehensive effects of balanced fertilization were better than those of conventional fertilization; balanced fertilization had a significantly higher marketable potato yield, 4 454 kg/hm², economic profit, 8 984 RMB Yuan/hm², apparent phosphorus element use efficiency reaching 33.1% and Vc content, 42.8 mg/kg. When using potassium chloride to replace potassium sulphate, the yield, economic profit and apparent nitrogen-element use efficiency(ANEUE) would be lower, in particular marketable potato yield and ANEUE decreased significantly at 0.05 level. It was suggested that under the conditions tested, potassium sulphate should be selected as the main potassium source.