In this test, study is made on the appearance of growth and development, fresh and dry weight, harvest index, photosynthetic rate, and stomatal conductance of different cultivars of potato under continuous light and high temperature. Results show that Denali, Snowship, Atlantic and La chipper all have fine productive potential and are eultivars suitable for planting in the closed Bioregeaerative Life Support System at the space station and/or lunar colonies. Of the three long-day cultivars (Denali, Snowchip and La chipper), Denali has many excellent biological characteristics, which result in high photosynthetic rate and harvest index. In addition, the plant body is neither tall nor broad and by making full use of radiant energy, has advantages of curly flowering and rapid tuber formation. It has been proved that good cultivars, such as Denali, can iucrease the utilizability of the Bioregenerative System in both time and space.