The aim of this study was to develop Cartoon Art Learning Media (CALM) to improve children's conflict resolution skill. The research method used was ADDIE (Analysing, Designing, Developing, Implementing and Evaluating) model. The subjects in this study were 27 (first trial) and 43 (second trial) fifth-grade students (with an average age of 11-12 years) at one of the public elementary schools in Karawang, West Java, Indonesia. The data collection instruments were in the form of a questionnaire, an assessment instrument and a conflict resolution ability test for fifth-grade elementary school students. The data analysis used is percentage and paired two-sample t-test for the mean to see the difference in the test results. In the evaluating stage, CALM was valid and effective to use based on experts' validation and trial results. Thus, it can be concluded that CALM can be used to improve children's conflict resolution skill.