OBJECTIVE: To understand the preputial hygienic practices and perceptions of Taiwanese junior-high-school boys and to determine what adequate advice should be given to parents, the boys, and medical practiotioners. MATERIALS AND METHODS: Many junior-high-school boys were randomized and enrolled into our study from March 1 to August 31, 2001. They were asked to fill in a questionnaire, which was divided into 2 major parts, including the participant’s baseline data, the subject’s preputial hygienic perceptions (a total of 6 questions), and the origins of genital hygienic information of these boys. Data sheets were collected, and t-test analysis and one-way ANOVA methods were used to assess the correlations between reported hygienic practices and perceptions. RESULTS: In total, 848 questionnaires were collected for analysis. The subjects’ ages were between 10and 13 years old; 91.7% of boys cleaned the prepuce by themselves; 68.9% of boys cleaned their foreskin everyday; and 18.2% of boys were previously circumcised. The most common reason for circumcision was “no special problem but on the suggestion of the physician” (37.1%); the reason that parents favored circumcision for their boys was “to prevent infection”. Boys received their genital hygienic knowledge from their parents (75.4%), teachers (26.3%), and medical practitioners (20.8%). The average score of the 6 questions was 3.50±1.73. As to outcomes, there was a significant difference between age and the hygienic perceptions, cleaning frequency and hygienic perceptions, and circumcision and hygienic perceptions (p<0.01). CONCLUSIONS: Most boys know how to care for their own preputial hygiene, although the hygienic perceptions of boys were not excellent. We believe that good hygienic standards can prevent penile problems as well as situations requiring circumcision. Perhaps it may be difficult to ensure the adequate genital hygiene in uncircumcised boys, so we provide some recommendations on the medical, hygienic, and educational aspects to parents, boys, and medical practitioners.