Background: Anxiety is a condition in which a person feels afraid or lost confidence for uncertain reason. Anxiety in teenager and school age children can significantly affect their daily activities, development, academic life, and social function. The situation can continue until their adulthood. Anxiety disorder is commonly experienced by adolescent. This disorder has affected 6-20% of children and teenagers in developed countries. One of the factors that cause anxiety is lack of knowledge on stress management. Therefore, the aim of this research is to know the effectivity of stress management module training on anxiety level among early adolescent. Method: This research is a quasi-experimental research that uses Pretest-Postest, Nonequivalent Control Group Design. The respondents of this research are 36 students of VIII grade in SMPN 4 Yogyakarta, whose age range from 12 up to 15 years old. The research instrument that is used is CERDAS (Young scholars work together in creating healthy Indonesia) stress-management module. Each respondent is given an informed consent, which then is given to their parents. The data is numeric scale that uses univariate and bivariate analysis using indepent test. Result: The result of independent test analysis is taken from the postest score of controlling group and intervention, which is 0,026 or 0 = < 0,05 witg positive mean difference. It shows that the postest score of students anxiety in intervention group is lower compared to anxiety level of students in controlling group. Therefore, there is a significant decreasing anxiety level of these groups. Conclusion: Stress-Management Module Training is effective in decreasing anxiety level of early adolescent.