Water and nutrients play important roles in the growth and yield of sugarcane while sugarcane responsesdifferently to water andnutrientsdependingon cultivars andcultivation area. Therefore, the effect of supplemental water and fertilizer rates on yield of three sugarcane cultivars grown on clay soil at Nakhon Sawan Province was studied, in order tofindoutsuitable waterandfertilizer management forsugarcaneproduction.Theexperimental treatments were designed as split plot with 4 replicates. The main plots consisted of three methods of supplemental water and fertilizer rates i.e. 1) fertilizing according to soil-based analysis recommendation, under rain-fed condition, 2) fertilizing at a recommended rate with supplemental water and 3) fertilizing about 1.5 time of the recommended rate with supplemental water. The subplots consisted of 3 sugarcane cultivars i.e. KK07-037, LK92-11 and Khon Kaen 3. Results showed that water and fertilizer management had no interaction with sugarcane cultivars for obtained yield. In addition, three methods of water and fertilizer management had no statistically different effect on yield. However, sugarcane with supplemental water and fertilizing at 1.5 times of the recommended rate had higher number of tiller of planted and the 1st ratoon canes when compared to those received fertilizers at the recommended rate under rain-fed condition and with supplemental water. The three sugarcane cultivars showed significantly different in yields which the KK07-037 planted cane had higher in yield but lower in CCS as compared to Khon Kaen 3 and LK92-11 cultivars. As a consequence, Khon Kaen 3 and LK92-11 cultivars resulted in higher sugar yield than KK07-037 clone. Therefore, planting of Khon Kaen 3 and LK92-11cultivars under rain-fed conditions andfertilizingat therecommendationrateof 12-9-18 kg N-P2 O5 -K2 O per rai was suitable for sugarcane cultivation in clay soil at Nakhon Sawan