A synergistic herbicidal mixture comprising A) at least one benzoyl compound of formula I or a salt thereof wherein R1, R3 are hydrogen, halogen, alkyl, halogenalkyl, alkoxy, halogenalkoxy, alkylthio, alkylsulfinyl or alkylaulfanyl; R2 is optionally substituted thiazol-2-yl, thiazol-4-yl, thiazol-5-yl, isoxazol-3-yl, isoxazol-4-yl, isoxazol-5-yl, 4,5-dihydroisoxazol-3-yl, 4,5-dihydroisoxazol-4-yl or 4,5-dihydroisoxazol-5-yl; R4 is hydrogen, halogen or alkyl; R5 is alkyl; R6 is hydrogen or alkyl; and B) a synergistically effective amount of at least one further herbicidal compound as defined in the specification, compositions comprising these mixtures, processes for the preparation of these compositions, and their use for controlling undesired plants.