This study examines the effects of instructors' academic disciplines and prior experience with the learning management system (LMS), Canvas, on current use. Our mixed method study collected data via an online survey from 557 instructors at two United States universities. Quantitative analyses found significant differences in instructors' use of Canvas by their academic discipline and prior Canvas experience. Content analysis of the open-ended responses revealed that, when reporting the strengths and weaknesses of Canvas, while instructors across disciplines reported common strengths, the weaknesses they identified varied according to the features they used for their specific disciplines. Our findings lead us to recommend routine evaluation and assessment of instructors' needs related to LMS. We suggest that, together with general LMS training, campuses design and offer discipline-specific LMS training to ensure instructors' needs for LMS based on their academic fields are addressed. Also, we propose that universities should design and offer basic and advanced LMS training programs for instructors with different levels of LMS experience.