This paper presents the results of a study on the tolerance of proso millet to herbicides (2,4-D + fluroxypyr; tribenuron-methyl + fluroxypyr; MCPA – 2-methyl-4-chlorophenoxyacetic acid; dicamba + triasulfuron) foliar-applied at the tillering stage of proso millet, at the maximum rate (100%) and at a rate reduced by 50%. Plots without herbicide application were the control treatment. The experiment was carried out on a loess-derived soil (soil class II) under the climatic conditions of the central Lublin region, Poland. The study proved that herbicide application in millet crops was justified, because the herbicides (in particular 2,4-D + fluroxypyr and tribenuron-methyl + fluroxypyr) contributed to a statistically significant improvement in the grain chemical composition (especially to an increased content of essential amino acids, fat, selenium, and o-dihydroxy phenols). Moreover, no residues of active substances of the herbicides were found in the millet grain samples analysed. The herbicide rate reduced by 50% proved to be sufficient to ensure appropriate quality of millet grain.