In this field experiment, three potato varieties of Favorita, Ziyu and Jizhangshu–12 were used as material, five light treatments (45% shading in certain growth stage, 45% shading in the whole growth stage, 70% shading in certain growth stage, 70% shading in the whole growth stage, no shading as control) were conducted to study the effects of different light treatments on growth dynamic, yield and its components of potato varieties by measuring plant height， dry matter, the content of starch in tuber，tuber numbers per plant, tuber yield and other main agronomic traits. The results showed that the change trend of the agronomic traits was: the control was the best, 45% shading treatments were better than 70% shading treatments, shading in certain growth stage were better than shading in whole growing period. The plant heights of potato varieties were significant different between the shading treatments and the control except Favorita. The main stem numbers decreased with the shading increase except Ziyu. The dry weight of Jizhangshu–12 declined more severely than those of Favorita and Ziyu potatos. 45% shading treating before tuber rapid expansion stage had significant effects on the tuber weight per plant of Favorita and Ziyu varieties and significantly decreased the commodity potato weight per plant of Jizhangshu–12. The tuber numbers per plant of Favorita and Ziyu, tuber weight of three varieties and commodity potato weight of Ziyu decreased significantly under 45% shading treated in whole growing period. The all characters of tuberization were significantly reduced under 70% shading treatments regardless of the shading stage. The yields of Favorita decreased by 41.6%–44.5% with both 45% shading treatments and there was not significant difference between the two treatments. 67.8% and 86.6% decreased with 70% shading treated in certain growth stages and whole growth stage, respectively. The yields of Jizhangshu–12 and Ziyu reduced less than 30% under 45% shading treated in certain stage, decreased by 57.4% (Jizhangshu–12) and 41.1%(Ziyu) with 45% shading treated in whole growing period, and decreased by 87.5% (Jizhangshu–12) and 78.8%(Ziyu) with 70% shading treatment in whole growing stages. In conclusion, Favorita and Ziyu, the varieties of early–maturing, of which yield and it’s components were less affected by light intensity, can adapt more readily to the cultivation environment of weak light and high humidity in southern winter.