Teratological study on pranoprofen, as antiinflammatory agent, was conducted by oral intubation in Sprague-Dawley rats. Pranoprofen was administered doses of 1.0, 2.5 and 5.0mg/kg/day and doze of 0.5mg/kg/day of Indomethacin was used as positive control. The rats were dosed from day 7 to 17 of gestation. At necropsy on day 20 of gestation, pathologically changes of gastroin-testinal system, liver and adrenal gland were examined at the high dose administered group. There were no differences between control and treated group on the number of implantations, the number of alive and dead fetuses, tail length, and external visceral and skeletal malformations.