Two field experiments were conducted at Sakha Agricultural Research Station during 2000 and 2001 summer seasons to investigate the effect of nitrogen fertilization and weed control treatments on annual weeds and sunflower growth and yield. Results indicated that as nitrogen fertilization increased up to 40 kg N / fed., the fresh weight of total annual weeds significantly increased. In the same respect, nitrogen rate had a significant effect on plant height, dry weight of sunflower plant and sunflower seed yield during both seasons. Application of butralin (Amex 48% EC) at 1200 g a.i/fed and oxadiargyl (Topstar 80% WG) at 160 g a.i./fed. surpassed other weed control treatments and reduced fresh weight of total annual weeds by 96.3 and 90.6% and by 88.9 and 73.7%, respectively in both seasons. Weed control treatments did not affect plant height, meanwhile it significantly affected the dry weight of sunflower plant and sunflower seed yield. Hence, butralin and oxadiargyl achieved the highest dry weight and increased seed yield by 595 and 536 and by 338 and 229 kg/fed, respectively in both seasons as compared to the weedy check. The interaction of nitrogen rate and weed control treatments was statistically significant on total annual weeds, dry weight of sunflower plants and sunflower seed yield. Hence, butralin or oxadiargyl achieved the lowest fresh weight of annual weeds, the highest dry weight of sunflower plant and the highest seed yield per fed. as compared to the unweeded check with the high nitrogen level. Therefore, to maximize the benefit from nitrogen fertilization, it is necessary to eliminate weed competition by using butralin, oxadiargyl or hand hoeing.