Paederus is a beetle belonging to the class Insecta, order Coleoptera, family Paederidae. It is distributed all over the world and often lives under grass or stones. It is most active from August to September, hiding during the day and coming out at night, flying under the lamp. If the venom in the insect contaminates the skin, it can cause acute dermatitis, which is extremely painful and can cause systemic reactions in severe cases. The skin lesions are erythema and pustules, which are in the form of strips, dots and sheets, with small pustules arranged in strips (one or more) or irregularly, which are very similar to the morphology caused by secondary infection after the skin is pierced by a bamboo stick. It can be diagnosed based on clinical manifestations and important characteristics. It can be treated with Daribo solution and 0.05% ethacridine (Livanol) cold wet compress.