Abstract: This paper is to compare two different promoting techniques of sprout-promotion of virus-free pre-basic seed potato. The result revealed that moist sand treatment is much better than normal diffused light treatment with respect to growth vigor and plant yield. The moist sand treatment had increased stem numbers, growth rate of stem (growth yield per-unit time) and plant height. The growth rate of main stems are same, but the leaf age of the main stems are one leaf faster than normal treatment. It also increased the number of tubers and improved the evenness of the shape of tubers. In view of virus-free seed potato production sequence (virus-free pre-basic potato seed→primary virus-free seed-potato→commercial seed potato) moist sand treatment has a good effect on shape eveness and yield of primary virus-free seed-potato.