The behavior of the Irish potato variety "Eigenheimer" in the State of São Paulo has been studied. This variety grows well under the soil and climatic conditions present in potato areas of this state. Eigenheimer is an early maturing variety and a good yielder. The tubers sprout readily in storage, permitting two plantings in a year to be made with same seed. It is susceptible to virus diseases, early and late blight, bacterial wilt, common scab, and root-knot nematode. It shows a tendency to develop second growth, and under rainy and hot weather is subject to internal brown spot. The tubers of Eigenheimer are deep-eyed, and a large percentage of the crop consists of average and small-sized tubers. Trie marketing value of the Eigenheimer potato equals that of Konsuragis, Parana Ouro, and Voran, being higher than that of white-fleshed varieties, but lower than the value of Bintje and Eersteling.