Single-shot ultrafast optical imaging is a technique that can characterize transient events under universal conditions, opening the door to the study of nonrepeatable and difficult-to-reproduce ultrafast phenomena. It is an essential tool for exploring unknown fields and has great scientific and technological value. This article introduces the research progress of single-shot ultrafast optical imaging in recent years, including the principles, technical characteristics, applications, advantages, and limitations of typical representative technologies. Specifically, we summarize the active detection methods, focusing on 15 representative techniques in 5 subcategories. Then, we provide a brief explanation of the passive detection methods. Finally, we review the applicable scenes and existing problems of various single-shot ultrafast optical imaging techniques and discuss the possible development trend in the future.