Abstract: The combined effects of different levels of nitrogen and potassium fertilizers on flowering and yield components of True Potato Seed (TPS) were investigated using crosses of ♀MF-II and ♂TPS-67. Twelve combinations of 3 N (0, 225 and 300 kg ha-1, respectively) and 4 K (0, 125, 175 and 225 kg ha-1, respectively) levels were applied to MF-II. Different levels of N or K showed significant effects on flowering and TPS yield. The combinations of N and K were also significant for most of the parameters except for the number of flowers inflorescence-1, number of berries plant-1 and number of TPS per small and medium size berry. Out of 12 treatment combinations, 225 kg N and 225 kg K ha-1produced the highest number of berries (22.7) and yield of berries plant-1 (207.2 g), whereas 225 kg N and 125 kg K ha-1 produced the maximum number of TPS berry-1 (196). The weight of 100-TPS increased with increasing N rate but decreased with increasing K rate; the results revealed that an inverse relation was observed between N and K on 100-TPS weight. The highest 100-TPS weight (83.8 mg) and maximum quantity (113.0 kg ha-1) of quality (> 1.18 mm) TPS were obtained with the application of 300 kg N and 125 kg K ha-1, while 225 kg N and 125 kgK ha-1 produced the highest TPS yield (145.3 kg ha-1). Our study showed that 300 kg N and 125 kgK ha-1 was the best combination for commercial production of quality TPS obtained from MF-II x TPS-67.