The invention relates to a mixed herbicide composition including mesosulfuron-methyl and flumetsulam. The herbicide composition employs mesosulfuron-methyl and flumetsulam as active ingredients, wherein the weight ratio of the active ingredients (flumetsulam : mesosulfuron-methyl) is 1:10-20:1. The herbicide composition has the advantages of low toxicity, weak sensitization, low poison to humans and animals, wide herbicide spectrum and significant synergistic effect for preventing and eradicating weeds, and is particularly suitable for prevention of various weeds in multiple crop fields, especially in wheat fields.