Assertiveness is the ability to express your emotions and needs without being aggressive and not violating the rights of others. If you are not assertive you may have low self–confidence and self–esteem, problems in social life. Students are the leaders of future generation and contributing ample for social development, so each student must have assertive behavior to succeed with more courage and self–confident in their education and future life. Objective: To assess the effectiveness of assertive training program among adolescents. Methodology: one group pre–test post–test control research design was used. 100 adolescents studying in the 10th standard were selected using Purposive sampling technique. Investigator developed self–structured assertiveness questionnaire for Data collection. Result: A statistically significant difference between post test assertive behavior score of experimental group and control group shows assertiveness training programme is effective to improve the assertive behavior[calculated t=19.72 (table value=1.9842)].