The prevalence of conflict among adolescents is very common. At times adolescents use violence to handle conflicts. As such, this problem needs to be addressed. This quasi-experimental study investigated the effectiveness of Peer Conflict Resolution Focused Counseling (PCRC) in promoting peaceful behavior (nonviolence and hostility, conflict resolution strategies, and peaceful friendship) among adolescents. Participants were 80 senior high school students in Mataram, Indonesia. Instruments used were Aggression Questionnaire (AQ) for nonviolence and hostility, Conflict Dynamic Profile (CDP) for conflict resolution strategy, and Human Relation Skill Questionnaire Scale for measuring peaceful friendship. Results showed that the experimental group had significantly higher scores than the control group on peaceful behavior. This implies that counseling, particularly PCRC was effective in promoting peaceful behavior among adolescents.