Cotton is an important industrial crop that is the natural raw material for many sectors such as textile, feed and oil industries. One of the factors affecting the yield and quality of cotton is weeds. Among these weeds, cocklebur (Xanthium strumarium L.) appears together with cotton and provides strong competition. In this study, field experiments were conducted at two different locations in 2020 to determine the efficacy of herbicides against cocklebur, which is a problem in cotton production, on yield elements in cotton and in cocklebur. The experiments were laid out according to the randomized block trial system with four replications. Different doses of the herbicides trifloxysulfuron sodium (TFS) (10, 15 and 20 g ha-1) and fluometuron (FLM) (2, 2.5 and 3 l ha-1) were used in the field experiments. As a result of the study, the effects of herbicide applications on cotton and cocklebur were evaluated on the 28th day in both sites. It was found that trifloxysulfuron- sodium was more than 90% effective in controlling cocklebur at different doses while fluometuron was found to be less effective at different doses. Regarding the effects of herbicide applications on cotton, trifloxysulfuron-sodium was found to cause no phytotoxicity at different dosages, while fluometuron showed phytotoxicity at different dosages. The highest cotton and fiber yields were obtained when 15 g ha-1 of trifloxysulfuron-sodium was applied. It was found that the effects of the applications on cotton fiber fineness, fiber length, and fiber strength were not significant.