bstract The main purpose of this study was to assess the factors influencing the implementation of HIV/AIDS related contents integrated in the preparatory school curriculum by using preparatory schools of North ~a Zone of Amhara Region and to come up with some possible recommendations. To achieve this purpose, jive preparatory schoois namely Haile Mariam Mamo, Enewari, Debresina, Shewarobit, and Arerti wer~ selected using purposive sampling technique by considering school staff size. From these five schools' 318 students through proportional simple random sampling, 66 teachers, 5 principals, and 5 Ant~-AIDS club heads through comprehensive sampling have been chosen. Questionnaires, interview, observation checklist and documents/examination papers/ were used to collect the necessary data. Data collected through close ended questionnaires has been presented, analyzed and interpreted using percentage, mean scores, frequency counts, X2 (chi-square) and tables. On the other hand, data o'btained through interview, observation, content analysis and open ended questions have been analyzed and interpreted qualitatively through descriptive statements and/or explanation. The findings of the study indicated that shortage of both pre service and in-service trainings of teachers on HIV/AIDS related contents &appr.opriate teaching methods to teach it, lack of principals' supervisory support, shortage of appro1'11e instructional materials, lack of students' interest, lack of teachers' interest, absence of HIV/AIDS related test items in examinations were some of the major influential factors that needs to be .. tackled for effective HIV/AIDS education in the classroom. Based on the summary of findings, conclusion was made and recommendation that could help to solve these influential factors forwarded.