There are direct relationships between the behavioral mechanisms and sensilla. To obtain a better understanding of the behavioral mechanisms in Omosita colon (Linnaeus) (Coleoptera: Nitidulidae), we investigated the types, quantities, and distribution of sensilla on the antenna and mouthparts of O. colon by scanning electron microscopy. The clavate antenna comprised the scape, pedicel, and nine segment flagellomeres and had six types of sensilla, including two subtypes of sensilla chaetica (SC), three subtypes of sensilla basiconica (SB) and sensilla trichodea (ST), and one type of sensilla cavity, sensilla styloconica, and Böhm bristles (BB). The chewing mouthparts of O. colon consist of the labrum, mandible, maxillae, labium, and hypopharynx and had seven types sensilla, including two subtypes of SC and sensilla placodea, seven subtypes of SB, and one type of BB, ST, sensilla coeloconica, and sensilla campaniformia. In this research, we also deduced the relationships between the sensilla on the antenna and mouthparts and their functions.