An experiment was conducted over a 2-year period at two sites in the central rainlands of Sudan under rainfed conditions at one location and under supplementary irrigation at the other to investigate the effects of cultivars and spacing on yield and yield components of sunflower. Row spacing had no significant effect on grain yield under either system of production. Under rainfed conditions, the late maturing cultivar Manchurian performed better under wider row spacing than Hungarian-A which is a medium late maturing variety. Size and number of seeds weie significantly affected by row width. It is argued that the choice of a row spacing for sunflower production on a commercial scale in dry regions should be evaluated in association with machine efficiency which is affected by plant height, stem circumference, head diameter and lodging, all of which were significantly affected by row width. Also the number of plants established per unit area of land differed between systems of farming.