In order to determine the prevalence of taeniasis in the Wufeng District of Hsinchu County, 341 school children from 2 primary schools and 748 Atayal aborigines from 4 villages were examined with a scotch tape perianal swab and by questionnaire and demonstration of proglottides. The infection rates of taeniasis and enterobiasis among the school children were 1% and 8%, respectively. The overall infection rate of taeniasis among the Atayal aborigines was 6%, and 189 previously treated and cured persons were also discovered. The highest rate was found at Taoshan Village (9%) and the lowest at Chulin Village (3%). The infection increased with age from less than 1% among those under 10 years of age to a peak of 11% for those over 50 years. The infection rate in males (7%) was similar to that in females (6%). Fourteen percent (43/305) of the families were found with one (91%) or two (9%) infected members. The infected persons had been eating raw meat and viscera of wild boar (70%), flying squirrel (65%), muntjac (58%), wild goat (56%) and the raw meat of other 6 kinds of wild animals. Passing proglottides in the feces (100%) and pruritus ani (91%) were the two most important clinical manifestations. One-third (33%) of the patients had passed proglottides for 21-30 years.