Assessment of buffalograss seed yield potential is limited. The available information indicated that seed production of improved cultivars ranged from 336 to 785 kg ha^-1. The major problems in buffalograss is seed yield potential, pest problems, and the overall management. Improving seed yield would be economically beneficial. This study was initiated to assess nitrogen (N) and phosphorus (P) effects on seed yield and seed sizes of Bowie. Three rates of each nutrient (i.e. N at. 48.7, 97.4, and 194.9 kg ha^-1; and P at. 24.4, 48.7, and 97.4 kg ha^-1) were applied in all possible combinations and compared to the untreated control. The 2004 analysis of variance showed no significance difference between the NP combinations for all seed sizes, though some were different from the control. Total seed yields ranged from 502.7 kg ha^-1 (i.e. at 194.9 kg ha^-1 N and 48.7 kg ha^-1 P) to 861.5 kg ha^-1 (i.e. at 194.9 kg ha^-1 N and 24.4 kg ha^-1 P). An increase in N rate increased bur yield of the different sizes. No definite trend was observed between P rates and bur yield. The 2005 yields were higher than 2004 ranging from 1153 to 1831 kg ha^-1. Significant differences among treatments were observed for all traits except bur yield. The highest yield, inflorescence height, color, density and quality were obtained at the highest rates of N. The combined analysis over two years also showed no significance difference among the treatments for bur yield. The highest yield over years was obtained at the highest rate of both N and P. These results indicate the potential to improve buffalograss seed production through manipulation of N and P fertilization.