High-speed imaging technology plays a significant role in various fields, including physics, chemistry, biomedicine, material science, and industry. Due to the limitations in charge storage and readout speed, it has been challenging to further enhance the frame rate of digital cameras based on electronic imaging devices. In recent years, with the development of new imaging technologies, the performance of ultra- and extreme-high-speed optical imaging has seen remarkable improvement, offering higher temporal resolution and spatial resolution, as well as larger sequence depth. Based on the imaging features, the representative new ultra- and extreme-high-speed optical imaging technologies developed in recent years are categorized into the direct imaging method and the coded computational imaging method in this paper. The concepts and principles of these novel ultra- and extreme-high-speed optical imaging technologies are introduced and discussed, along with a comparison of their respective advantages and limitations. Finally, we provide an outlook on the development trends and prospects in this field. The purpose of this review is to assist researchers in gaining a systematic understanding of the fundamental knowledge of ultra- and extreme-high-speed optical imaging technologies, the latest research trends, and the potential applications, offering a reference for scientific research in this field.