Two sugarcane cultivars, ROC22 and YZ05-51, were grown in a pot trial that were conducted in greenhouse. Their roots distribution, cane yield and plant height under three water stress condition, moderate stress: 70% of field capacity; severe stress: 50% of field capacity; check: 85% of field capacity, were investigated. The results indicated that the yield had a significant positive correlation with root length, total root volume, root surface area, root fresh weight, and root dry weight. Plant height and cane yield of two cultivars in water stressed treatment were lower than the check treatment, however, their total root length, root surface area and total root volume in moderate stress treatment were much higher than the check treatment. In the most water stress treatment, the total root length, root surface area, total root volume and drought resistance index of ROC22 were much higher than that of YZ05-51, and the roots of ROC22 distributed more thanYZ05-51 at the soil layer.