Abstract: Objective To explore the impact of school-based AIDS prevention education on the knowledge and attitudes of the students.Methods Grade 7 and Grade 10 students from nine secondary schools of Shenyang participated in this program.AIDS-related knowledge and attitudes of the students were surveyed by self-administered questionnaire anonymously before and after education.The health education teachers were trained and implemented the program in their schools.Results After education,average score of AIDS prevention knowledge of the students was improved significantly(from 6.67 to 10.98.full score 15).The percentages of the students who were opposed to male and female youth premarital sexual behavior increased from 47.8% and 52.0% in pretest to 57.3% and 63.0% in pos-ttest respectively,and the percentage of the students who expressed that they would like to be in the same classroom with someone who infected with HIV also increased from 5.1% in pre-test to 22.6% in pos-ttest.Conclusion The school-based AIDS prevention education program improves basic knowledge and changes some attitudes of the students regarding HIV/AIDS.But more attention should be paid to the attitudes of the students regarding AIDS prevention besides the basic knowledge in school-based AIDS prevention education in the future.