A pool-culture experiment was conducted to study the effects of potassium humate on the growth and active oxygen metabolism of ginger root. The results showed that applying potassium humate increased the root fresh mass and root vigor significantly, and promoted the root growth especially in later period. Potassium humate application obviously increased the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), decreased the content of MDA, and delayed the senescence of ginger root. After applying potassium humate, the soluble protein content in root was increased by 49.18%, 25.89% and 13.26%, and the yield was increased by 61.29%, 48.13% and 9.92%, respectively, compared with the treatments CK, same application rate of humic acid, and same application rate of potassium monoxide.