Corn is the largest crop in Croatia. An important limiting factor of production are weeds. Weeds his presence regularly inflict great damage to corn, which is why the application of herbicides regular measures in breeding technology. A significant group of herbicides registered for use in corn are carotenoid biosynthesis inhibitors. In Croatia, in this group registered herbicides mesotrione and tembotrione. The herbicide topramezone is not yet registered for use, but its broad purpose of the control of annual broadleaf weeds in corn presents it as potentially a good exchange today prohibited herbicidal active substances. The aim of the research conducted at the Faculty of Agriculture experimental Šašinovečki Lug was to determine and compare the effect of the herbicide mesotrione, tembotrione and topramezone, applied at the recommended dose and twice that in the crop of corn. All treatments were applied in post-emergence period of time. Impact assessment of treatment was determined by visual assessment of damage (0-100%) and determine the number of animals and fresh aboveground mass of weeds. The research results indicate that mesotrione and topramezone in both the administered dose satisfactorily reduce the number of individuals and aboveground mass of annual broadleaf species (Chenopodium album, Polygonum persicaria, Ambrosia artemisiifoli and Amaranthus). The effect of the reduction of (94.4% and 100%) and narrow-leaved weed nadzemene weight of Echinochloa crus-galli (99.2% and 100%) was satisfactory just applying herbicide topramezone and the dosage of both examined. Mesotrione and tembotrione in any of the applied dose not satisfactorily reduce the number and mass of bone.