The purpose of this study was to provide the basic data for developing a program for effective health education about AIDS (Acquired Immunodeficiency Syndrome) by investigating the knowledge and attitudes of middle and high school students about AIDS. The subjects were 476 middle school students and 658 high school students from Seoul and Kang Won province. The data were collected from November 19 to December 18. 1996. using a 56-item questionnaire. and analyzed by SAS program for t-test. x2-test. and pearson correlation coefficients. The results were as follows : 1. High school students had more knowledge than middle school students about AIDS. 2. Male. students from Seoul. and students who had drinking experience and smoking experience among middle school students. and male. students from Seoul. and students of non-coeducation among high school students were more knowledgeable about AIDS. 3. Misconceptions about the transmission of AIDS through non-intimate contact were especially common among middle school students. And a high proportion of middle and high school students knew very little about the symptoms of AIDS. 4. High school students had more positive attitudes toward AIDS than middle school students. 5. Students from Seoul and students who had smoking experience among middle school students. and students from Seoul and non-coeducation and students who had substance use experience among high school students were more positive attitudes about AIDS. 6. Most of the middle and high school students agreed that there is a need for AIDS education. 7. Middle and high school students reported that had learned about AIDS mostly from TV. Since students in the middle-school age group are especially at risk for developing AIDS­related behaviors. this study findings suggest that it is crucial to develop school-based AIDS education programs that help students acquire the knowledge and attitudes to adopt and maintain behaviors that reduce the risk of HIV (Human Immunodeficiency Virus) infection and other related health problems.