An analysis of tuber roots yield and nutritional characteristics for 10 lines of jícama (Polymnia sonchifolia Poepp et Endl.) was carried out under the environmental conditions of Santa Catalina Experimental Station (12 degrees C of temperature and 3,100 m above sea level). The following average mean values were obtained: A fresh tuber root's yield from 29,755 to 73,558 kg/ha with 41,547 kg/ha of average, while the yield of the useful part (roots without skin) was from 24,309 to 60,097 kg/ha with 33,944 kg/ha of average. On the other hand, average mean values of 3.7% of protein, 3.5% ashes, 1.5% fat, 3.4% fiber, 2.2% potassium, 0.12% phosphorus, 96 micrograms/100 g iron, and 390 micrograms/100 g zinc, were obtained from the edible root samples. Besides, we obtained average values of 2.47, 2.12, 1.63 and 2.51 g/100 g of fructose, alfa glucose, beta glucose and saccharose, respectively, on edible root samples with skin, for the 10 lines studied. All these analyses were reported on a dry basis.