The objective of this study was to know the response of four cotton varieties to plant density in the narrow row cotton production system (0.70 m). In 1997 and 1998, three early (CIAN Precoz, CIAN Precoz 2, and CIAN 95) and a late (Deltapine 5.690) cotton varieties were evaluated at four plant densities; 70.000 (check), 82.500, 95.000 and 108.000 plants/ha. To get these plant densities a distance between plants of 20, 17, 15, and 13 cm was given, respectively. The characteristics measured were the lint yield, the earliness, and the yield components. Year and variety effects on lint yield were detected. In both years the early cotton varieties showed higher lint yields than the late variety. The best variety was CIAN Precoz 2 and its lint yield was 15% higher than the yield of Deltapine 5.690. The yield of CIAN Precoz and CIAN Precoz 2 increased as plant density increased, and the other two varieties showed their higher yield potential at a plant density of 825.000 plants/ha. At first harvest the early varieties yielded between 800 and 1.200 kg of seed‑cotton/ha more than the late variety. The boll number/plant decreased as plant density increased.