Since the COVID-19 pandemic hit the world, many problems have been caused by accompanying effects, including impacts in the field of education. This study aims to explore the problems faced by physics education study program students in modern physics lectures in online learning during the COVID-19 pandemic. The method used in this study is a qualitative description with a questionnaire as a data collection technique. A total of 28 students who contracted modern physics courses and two lecturers who taught modern physics courses were participants in this study. The collected data were analyzed descriptively-qualitatively. After data analysis, several problems faced by students in attending modern physics lectures can be identified, namely: difficulty mastering concepts, internet signal interference, less interesting/monotonous learning, and never doing modern physics practicum. Limited tools are the main factor in the inability to carry out practicum. Even though practicum allows students to master abstract concepts of modern physics. Based on these findings, further research can be carried out that can facilitate students to more easily master modern physics concepts that are integrated with a practicum in the learning process.
Keywords: learning problems, prospective teachers, lectures modern physics, covid-19 pandemic