The purpose of this study is to develop an assessment framework for evaluating the students’ achievement in integrated education. The focus group interview involved seven experts who had over ten years’ experience in integrated education. Six focus questions were developed based on the written questionnaire done by these experts. The interview was transcribed, analyzed and categorized into consensus (C), disagreement (D) and individual/idiosyncratic (I) responses. The interviewees agreed on the importance of change in action, emphasis on aesthetic sensitivity, composition of four categories (cognition/process/affectivity/ action), and uniqueness as variables for the effect of integrated education. However, there was a lack of consensus on whether the basic knowledge and process in each discipline should be included as assessment factors or not. There were agreements on the need to distinguish and redefine the thinking skills, but the broad conclusion was not made. As a result, four categories and fourteen variables were suggested; integrated thinking (critical thinking, associative thinking, creative reinterpretation skills), integrated process and skills (problem solving skills, design and improvement, media literacy, cooperative communication skills), attitude toward integration (willingness and belief for integration, comprehension and tolerance about difference, interests in various disciplines, aesthetic sensitivity), and holistic approach to participation and practice (recognition of value and change of action, practice based on connectivity among individual, community and environment, expansion and reproduction of practice with an integrated view). The educational use of the assessment framework is also discussed in the present study.