Nine cases of human infection with Strongyloines stercornlis are reported among patients admitted to the Seoul Paik and Sang-Kye Paik Hospitals, Inje University, from April 1990 to Junuary 1992. The Patients, 7 males and 2 females acted between 50 and 70, either had the history of long term use of steroids for management of arthritis, or were complicated with other chronic diseases such as hypertension, liver diseases, psychotic disorders, and gastrointestinal problems. All of the nine patients revealed rhabditoid larvae of S. stercorolis in fecal examination. A 57-year-old woman who complained of arthritis and abdominal discomfort, was treated with albendazole and mebendazole, and on the 4th and 5th treatment day 220 parasitic adult females were collected from the diarrheal stool. The patient had a long history of administration of steroids for treatment of arthritis, and seems to have suffered from hyperinfection syndrome due to autoinfection with S. stercordis. This is the 3rd report on the recovery of parasitic adult females of S. stercoraLis in Korea. Key words: Strongyloines stercoralis, strongyloidiasis, hyperinfection, rhabditoid larva, parasitic adult female