Terahertz (THz) imaging technology, as an emerging imaging method, has the advantages of being non-invasive, non-destructive, and high-resolution, and has achieved significant progress in recent years. This paper reviews and analyzes terahertz imaging technology from the perspectives of technical approaches and current research status. Based on the type of signal source, the technical characteristics of pulsed terahertz imaging and continuous-wave terahertz imaging mechanisms are compared and analyzed. On this basis, the paper focuses on the technical solutions with super-resolution and high-speed imaging capabilities, analyzes their current development status, and discusses their advantages in future terahertz imaging scenarios. Finally, the challenges of application-oriented terahertz imaging technology are summarized and prospected.