The invention relates to a chemical herbicide composite with a synergistic effect and application thereof, belonging to the technical field of herbicides. The aim of the invention is to provide the herbicide composite for corn and wheat fields, which has the characteristics of synergistic effect, wide grass-killing spectrum, rapid herbicide effect and good effect on malignant grass, and can delay the herbicide resistance of grass. The technical key point is as follows: active ingredients of the herbicide composite are thifensulfuron methyl, fluroxypyr and tribenuron with the mass ratio of (0.5-25): (0.5-25): (0.5-25). The thifensulfuron methyl, fluroxypyr and tribenuron are compounded, thereby overcoming the defects that a single preparation is slow in weeding and has poor effect on the malignant grass, improving the herbicide effect, enlarging the grass-killing spectrum, prolonging the lasting period, reducing the number of application times, being more friendly to environment and greatly reducing the cost; as long as the herbicide composite is applied once in a growth season, the damage of the malignant grass can be controlled in the whole growth season, and the yield increase effect is obvious; and the labor intensity is alleviated, the environment pollution is reduced, and the society benefit is obvious.