This study was conducted to identify rate of nitrogen, phosphorus and potassium appropliate in order to improve cotton productivity, quality seeds and propagation coefficient in in Ninh Thuan province in winterspling dry season. The results showed that both cotton valieties TM1KS and VN36PKS gave the highest gained the yield and the highest propagation coefficient in the formula fertilizer at the rate of 120 kg N + 60 kg P2O5 + 120 kg K2O per hecta respectively 2.53 ton/ha and 160.3 times for like TM1KS
2.16 ton/ha and 176.5 times for like VN36PKS. The rate of fertilizer N, P2O5 and K2O different little effect on 100 seed weight of both valieties TM1KS and VN36PKS, however, germination and germ growing power of two valieties increased with increasing fertilizer dose and ratio of N, P2O5 and K2O and peaked in the application of 120 kg N + 60 kg P2O5 + 120 kg K2O per hecta germination rate of 95.0 percent and health grows germ (83.0 percent) for like TM1KS
94.7 percent and 79.7 percent for the same VN36PKS.