The article presents the results of the research conducted in order to determine the manifestation of the performances of the trait for the weight of 1000 seeds in three-generation populations of G. hirsutum L. varieties and lines cultivated in the years 2020-2022 in the soil and climate conditions of Tashkent region of the Republic of Uzbekistan. At the end of the article, it was concluded that the analyzed C-6524, Bukhara-102, Sultan, Mehnat, Yulduz and C-8290 varieties differ positively compared to standard variety Namangan-77 and other genotypes.