The good health is the guarantee for desirable potato seeds yield. In the practical growing period, some fungi diseases have some chances to be infected, impacting on the final harvest. The most common fungi is Phytophthora infestans, a leading serious fungus for yield reduction, it’s mainly infected by asexual spores produced during the balloon spread. At early stages, brown or deep purple spots will sprouted, slightly sunken lesion, usually less than 1em, reddish brown skin. With a lapse of time, the spot will spread to the surrounding part, causing dry rot or wet rot, depending on the humidity. The early appearance is not easy to discover, however, once affected and being planted in the field, it will spread and infect the neighboring seeds rapidly. There will be no solution if it’s cold or wet. Therefore, before planting, it’s very important the visually inspect the potato seeds for any sunken lesion or purple spots to avoid fungi infection.