The present study aims to investigate the correlation between university students' satisfaction and anxiety in online classes during the COVID-19 pandemic in Iran. To this aim, using a random sampling method, a sample of 430 male (n=150) and female (n=230) university students were selected at Ayatollah Borujerdi University. They filled out two questionnaires: one measuring their satisfaction and the other one measuring their anxiety in online classes. To triangulate the quantitative data, 22 university students completed a reflective written statement. To analyze the collected data, a Pearson correlation analysis, a multiple regression analysis, and a thematic coding analysis were used. Findings evidenced a moderate negative correlation between the participants' satisfaction and anxiety in online classes. Additionally, results documented that instructor, technology, and outcomes factors had the largest effects on the participants' anxiety in online classes. Complementary with the quantitative findings, the results of the reflective written statements yielded four overarching themes, including 'instructors are facilitators', 'technology makes learning easier', 'outcomes are more promising', and 'interacting with others is poor'. Finally, in light of the findings, a range of implications is suggested.