The intestinal nematode Enterobius vermicularis is the most common metazoan endoparasite in humans, with humans being the only host. But complicated perianal granulomas due to Enterobius are unusual. The literature reports only 13 previous cases of enterobiasis presenting as perianal mass or abscess. We describe an additional case of a perianal mass caused by granulomatous inflammation containing Enterobius vermicularis eggs and dead bodies in a 7-year-old boy. The lesion was located in the anus and measured 2 1 cm. Clinical impression was lipoma and excisional biopsy was done. Microscopic examination revealed necrotizing granuloma which contained several 50~60 20~30 micrometer sized eggs which were identified as those of Enterobius vermicularis. The adult worm could not be identified with clarity due to necrosis.