Field experiments were conducted to study the effects of different potash (K) application rates on growth, uptake of potassium, nutrition qualities and profit of ginger (Zingiber officinale). Results showed that appropriate K application rates could significantly promote ginger growth, increase rhizome yield, raise K concentration and uptake, and improve nutrition quality and profit. Ginger rhizome yield increased by 13.0%-27.2% and 22.3%-37.7% with averages of 22.5% and 28.7% at two sites two years respectively, with a parabolic relationship between rhizome yield and K application rate, and the highest rhizome yield was obtained by the treatment of medium K application rate of K450. K concentration and K uptake in ginger shoot, rhizome and total plant increased by 33.4%-210.7%, 2.9%-70.8% and 18.4%-139.9%, as well as 64.5%-342.2%, 31.3%-118.7% and 48.5%-209.0% respectively, when different potash rates were applied. The content of rough protein, vitamin C, and soluble sugar in ginger rhizome enhanced obviously and the treatment of K450 reached the peak when the suitable K rate was applied. The profit increased by 13,?626-23,?286 yuan/hm2 and the value cost ration reached (2.27-12.60)︰1 compared the treatments of K application to the control.