摘要:Science educators have highlighted the need to develop students to integrate knowledge across science disciplines to address real-world issues. However, there has been little research about the development of interdisciplinary assessment instruments. In this research, the instrument that measures the level of upper-secondary school students’ interdisciplinary understanding of environmental issues was developed and validated based upon Wilson’s Construct Modeling framework. After a pilot testing, the revised assessment instrument of interdisciplinary understanding covering five typical environmental problems comprised 14 multiple-choice questions and four constructed-response questions. Five hundred twenty-three eleventh graders, including 279 boys and 244 girls from mainland China, made up the research sample. The partial credit Rasch analysis has verified the reliability and validity of the interdisciplinary understanding instrument. In addition, the results of cluster analysis revealed that over half of the students could use some partially accurate scientific concepts and principles from two or more disciplinary perspectives to deal with a specific environmental issue. The validated instrument can provide insights for assessing and developing upper-secondary school students’ interdisciplinary understanding in science education.