This study aimed to develop an instrument, named the inquiry-based laboratory classroom environment instrument (ILEI), for assessing senior high-school science students' preferred and perceived laboratory environment. A total of 262 second-year students, from a senior-high school in Taiwan, were recruited for this study. Four stages were included in the development of the ILEI: (1) item formulation, (2) content validation, (3) construct validation and (4) reliability calculation. The study revealed that the ILEI was valid and reliable. Most students showed a preference for a student-directed and teacher-guided hybrid learning environment. The development of the ILEI is likely to help researchers and teachers to more effectively understand student views of the laboratory classroom environment. Our profound hope is to utilise ILEI to improve teachers' assessment and students' learning in inquiry-based laboratory classroom environments.