Online impulse buying has drawn increasing scholarly attention across disciplines. However, little effort has been made to evaluate the status of research and consolidate the findings in the literature. To address this research gap, we conducted a systematic review of studies of online impulse buying, and used the Stimulus–Organism–Response (SOR) framework to identify and classify the factors that affect online impulse buying. We then built a conceptual framework to explain the interrelationships between the three key elements of online impulse buying. Finally, we discussed the future research directions and implications for research.