A three year multi-point field experiment from 1999 to 2001 was conducted at six sites of Shajiang black soil in the Huaibei plain.The results showed that the crop of ginger responded positively to Potassium application in both yield and quality.The yield of ginger increased by 15.3%~58.4% with an average rate of 29.8%.The yield increasing effect of Potassium fertilizer was quite high with two rates of Nitrogen application.Coupled with a high rate of N,increased Potassium application rate may show higher yield increasing effect.A notable negative relationship between increase institute yield of ginger tuber per kg K₂O applied and soil K content and K application rate was observed.The proper Potassium application rate for ginger was 375~450 kg K₂O/hm² in the Shajiang black soil region of the Huaibei plain.Potassium fertilizer application could effectively enhance the content of Vitamin C and soluble sugar and reduce nitrate content in ginger tuber conspicuously,resulting in improvement of inner quality,and raising economic benefit of growing ginger substantially.For the experiments conducted at the four sites in the three years,the income was increased by 7946~11065 Yuan/hm² averagely,and the value cost ratio for Potassium application was 10.4~22.2:1.