Field experiment were conducted in acidic brown hill soils (Palehumults) of Fagu (Simla) during 1975 and 1976 to find the optimum K dose and and its best method of application to potatoes. K application increased the tuber yield significantly, mainly by increasing the size of the tubers. The response was best depicted by the quadratic equation and curve. The optimum K dose worked out was 77 to 79 kg/ha. The K application increased K concentration of the leaves and K uptake by the tubers but decreased the dry matter content of tubers. Furrow and band placement of K fertilizer was found to be better than broadcasting.