Abstract: Objective To evaluate the feasibility and effectiveness of a reproductive health program with information, education and communication (IEC) method among junior middle school students. Methods Investigation was performed by the stratified cluster sampling method. Self-report questionnaires were given to junior middle school students who were randomly included from 16 classes of 8 middle schools in Shanghai. A 3-month intervention with IEC method was conducted, which included activities as issuing intervention material, hand-copying paper competition, debating discussion, knowledge contest, scene plays and so on. Participant teachers had been trained for organization of these activities. After that, a second investigation by questionnaire was made both in intervention and control groups and then effect evaluation was done on the basis of the results of the two investigations before and after intervention. Results Compared with control group, knowledge scores of intervention group were improved significantly after the intervention.The general knowledge scores were increased from 42.3 to 61.3 (P<0.01), which was apparently higher than that in control group. At posttest, the intervention group students' premarital sex attitude was more conservative compared with the control group,with the scores being increased from 66.7 to 73.9 (P<0.01). The intervention group students' scores of having premarital sex and safe sex intention were increased from 77.7, 68.7 to 89.9, 87.3 (P all<0.01). There were about four fifths students who expressed that they were satisfied with the intervention content, format, time schedule, and benefited from it. Conclusion The school-based IEC method can change the premarital sexual behavior intention in some students and some others tend to have safe sex. Short-term effect of intervention is apparent, but the long-term impact of the intervention on the students still needs to be further investigated and confirmed.