Background: Violent behavior is a form of attitude, thought behavior both verbally and non-verbally as well as non-physically that can hurt yourself, others and the environment. The study aims to determine the effect of assertiveness training in shortening the length of treatment and reducing the risk of violent behavior symptoms in the Banyumas Regional Hospital maintenance room, knowing the effect of assertive training in shortening the length of treatment and reducing the risk symptoms of violent behavior. Research Methods: The method used is "Quasi Experiment Pre-Post Test With Control Group" with assertive exercise treatment. The study sample was 34 patients with risk of violent behavior, namely 17 respondents in the intervention group and 17 respondents in the control group with consecutive sampling. Risk of violent behavior used is the respondent demographic data questionnaire, observing behavioral responses, observing social responses, cognitive response questionnaires and observing physical responses in the form of a Likert scale to assess the validity and reliability of data gathering tools before the data is used. Differences in risk of violent behavior are then analyzed by t test. One of the therapies that can be given to clients who experience a risk of violent behavior is assertive training. Results: The results showed the risk of violent behavior in groups that received assertive training can decrease behavioral, cognitive, social and physical responses (p value <0.05). Assertive training is proven to reduce the risk of violent behavior on the client the risk of violent behavior and is recommended to be applied as treatment therapy in treating clients with risk of violent behavior. Conclusion: Assertive exercise has a significant effect in reducing behavioral, social, cognitive, and physical responses to violent behavior.