Abstract: Several cases of dermatitis were observed among students and workers in the new student hostel of Benha University, Benha, Egypt during the summer and fall seasons in 1996 and subsequent years. Males and females were equally affected. Age, occupation, race, food habits, drug-taking, type of soap or cosmetics used did not show any relationship to the problem. Clinical and laboratory investigations including urine, stool and blood analysis were all normal. The skin lesions started by burning and slight itchy erythematous patches that soon vesiculate with increased intensity of itching. Later, the lesions desquamate leaving hyper pigmentation. Strikingly, the lesions were bizarre shaped suggesting a contact with certain secretions produced by an insect. The most common body parts involved in all these cases were the neck, followed by arms, legs, face, chest and shoulders. The causative agent in all these cases were found to be the tiger beetle Myriochile melancholica F. (Cicindelidae, Coleoptera) which were seen in rooms especially during night crawling on the bare body parts of sleeping students. The highest number of insects and cases were recorded in the 2nd floor. The mechanism by which the insect provoke skin symptoms is still a matter of debate. So far, this is the first published report of an outbreak of dermatitis caused by tiger beetles and it is a good example for the effect of urbanization on human health.