Purpose: In this study, it was aimed to improve the hand washing behaviors of a group of secondary school students. Material and Methods: The study group comprised of 212 secondary school students (6th, 7th and 8th grades) in the catchment area of Yeşiltepe Health Care Center in November 2006. Onehundredand eightyfour students participated in this study (participation rate= 86.7%). The students were divided into "intervention" and "control" groups. A checklist including 10 steps was used to evaluate the hand washing behaviors of the students. .Before and after. assessment was applied for analyzing the success of the intervention. McNemar and chi square tests were used for data analysis. Results: There was no statistically significant difference between the age, gender, having sibling, family type, education status of parents between intervention and control groups. Students in the intervention group did five out of 10 steps in the check list successfully compared to the students in the control group. There was no statistically significant difference between control and intervention groups in terms of hand washing steps before the training whereas the groups differed after the training. Conclusion: The students. hand washing skills were increased. Skill-based training methods are recommended to be used for teaching.