The aim of this study is to produce a product in the form of an assessment model for autistic children through art therapy to improve their concentration ability in inclusive early childhood education schools. This research is conducted as a Research and Development (R&D) exploration employing the ADDIE model, which involves (1) analyzing the need for implementing assessments in the field, (2) designing assessment models based on the results of field analysis, (3) developing the assessment model through validation and revision towards a product that is ready for trial, (4) implementing assessment models for autistic children in five inclusive early childhood education schools in Surakarta to test the feasibility of the model, and (5) evaluating to determine the final product. The population consists of autistic students from inclusive early childhood education schools in Surakarta. Research instruments include interviews/observations, questionnaires, tests, and product validation instruments. Data analysis was conducted to observe the mean difference between the two samples using a t-test. Based on the independent sample test, a significance value (2-tailed) of 0.019 was shown. In other words, autistic children who undergo assessment with an art therapy approach exhibit better concentration skills compared to autistic children who undergo assessment without the application of the art therapy approach.