The head louse infestation had been no problem since 1960s in Korea. However, the present study revealed highest infestation rate among the primary school children in Seosan-gun, Chungnam Province in July 1983. The cases of louse positive were determined by identifying the adult worms and/or their nits on scalp and hairs. The overall louse positive rate among 615 children examined was 73.5 percent. The rate was higher in girls (78.8 percent) than in boys (67.6 percent) and was highest in 3rd-4th school grades. It was observed that the more the number of family members the higher the infestation rate of children. The positive children were treated with 20 percent benzyl benzoate solution after the test for louscidal effect in petri dish. However, establishment of intensive control measure is needed to prevent further infestation.