The purpose of this study was to examine why college students procrastinated in online courses from a selfregulated learning perspective. A sample of 207 college students participated in this study. Using path modeling, the results showed that students’ perceived content relevance and technology usability indirectly predicted academic procrastination through the roles of task value and emotional cost. Conscientiousness was also an important predictor of academic procrastination. Perceived instructor engagement and peer interaction did not predict academic procrastination. These findings revealed that academic procrastination in online courses was a complex phenomenon and stemmed from the interrelationships between college students’ per ceptions of learning context, personal characteristics, and motivational beliefs. Practical implications for addressing academic procrastination in online courses are discussed in this paper.