An in-depth analysis of today's online biochemistry learning is required to ensure better learning in the future. As a skill that students need to enter the world of work, critical thinking remains a goal in higher education. To develop critical thinking, students need to self-regulate by developing their self-regulated learning (SRL). This study aims to analyze students' critical thinking and SRL during online biochemistry learning. The research sample comprises 54 University of Mataram students. The data on critical thinking and SRL were gathered using tests and questionnaires. Supporting data were collected from observations on the Moodle platform, which was used as a learning tool during the learning process, and free-response data. The results revealed low average scores for three components of the students' critical thinking in online biochemistry learning, namely hypothesis testing, developing conclusions and argument analysis. Among the indicators, metacognitive skill had the highest average score and help seeking had the lowest average score in the SRL measurement. Students' low critical thinking in online biochemistry learning may be caused by a lack of student-student interaction.