Abstract: To investigate the effect of split application of nitrogen on cotton yield and its components for medium stapled commercial cotton (Gossypium hirsutum L.) variety MNH554, a field trial was carried out at Cotton Research Station, Multan during 1998 to 2000. Ten nitrogen levels viz., 0, 56, 84, 112, 112, 140, 168, 168, 196 and 224 kg N ha-1 were tested in Randomized Complete Block Design having three replications. Nitrogen was applied in split doses at planting. Ist irrigation, flowering and boll fermentation. 56 kg P2O2 ha-1 was also applied as a basal dose . N168 kg ha-1 proved superior over others when split applied in three equal doses i.e., 56, 56, 56 kg N ha-1 at Ist irrigation, flowering and boll formation stages. This produced a significant increase in plant height, bolls per plant, boll weight and seed cotton yield. On the average of three years 168 kg N ha-1 gave 212.8% increase in seed cotton yield over O.N.