Scientific research work on the creation of early maturing medium-fiber varieties of cotton was carried out by soil and climatic conditions of the Karshi steppe of the Kashkadarya region. In newly created medium-fiber cotton lines, the maturation period is 7-12 days shorter, the opening speed of the boxes is 2,0-3,2 pieces larger, the share of open boxes on September 1 is 7,5-12,2% higher, the yield increase by 10,1-12,6% more than the standard variety. For the best lines, the fiber yield was 37,0-37,6%, and the fiber length was 34,1-34,6 mm.