The quality of cotton fiber is a fundamental criterion for determining the commercial value of the product, being influenced by the conditions of cultivation. The study aimed to evaluate irrigated and non-irrigated cultivation systems and the management of silicon fertilization on cotton fiber characteristics. The experiment was carried out in the field in Selvíria-MS, in the 2017/2018 agricultural crop. It was adopted a randomized block design, in a 2x6 factorial scheme, with two cultivationconditions (irrigated and rainfed) and six doses of Si (0, 50, 100, 150, 200 and 400 g ha-1), with four replications. Seeds of the genotype TMG 11 WS were used. Irrigation was carried out with sprinklers spaced at 6x6 m. The application of Si via leaf was carried out at 50 and 70 days after emergence. From thecotton fiber, the characteristics of length, micronaire, strength, uniformity, elongation, reflectance, yellowing, degree of leaves, impurity and impurity particles were analyzed. The data submitted to analysis of variance by the F test, the means compared for the cultivation condition, and regression analysis for the amount of Si. The cotton fiber in irrigated cultivation showed improvement in the characteristics resistance, reflectance and yellowing.The application of Si via leaf reduced the leaf grade in the cotton fibers.