Sweet corn (Zea mays saccharate Sturt) is generally cultivated in monoculture with a wide spacing stimulates the increasing of the weeds growth surrounding the maize. Weed control mostly carried chemically which the impact could remain disadvantage to the environment. One of the efforts to reduce the negative impact is culture by applying the intercropping system. The objective of the research was to determine the diversity of weed and types of legumes that are effective to suppress the growth of weeds in intercropping. The research was conducted using a single factor experiment design that was arranged in a randomized completely block design (RCBD) with three blocks as replications. The treatments were five types of legumes i.e groundnut, soybean, kidney bean, cowpea and mungbean, added monoculture of sweet maize and legumes as controls. The results of the research showed that there were 33 species of weeds in intercropping with dominant weeds are Cyperus rotundus, Cynodon dactylon, Physallis angulata and Phyllanhus niruri. The existence of all species of legumes among sweet corn on intercropping can suppress the growth of weeds and not reduce the yield of sweet corn. The highest ability to suppress weeds is intercropping sweet corn+cowpea