In recent years, terahertz imaging has been widely used in biomedicine, security screening, and agricultural product inspection. However, the resolution of conventional terahertz far-field imaging techniques is limited to the millimeter level because of the diffraction limit. Terahertz near-field imaging techniques can break through the diffraction limit and achieve high temporal and spatial resolution imaging at the micro-nano level. This paper first outlines the basic principles of terahertz near-field imaging technology and subsequently details several methods to realize it. In addition, applications of terahertz near-field imaging technology in biomedicine, material science, and cultural relics detection are introduced. Finally, future challenges and development directions of terahertz near-field imaging technology are outlined. With continuous development and improvement, terahertz near-field imaging technology is expected to expand as part of deeper applications in additional fields.