Terahertz focal plane array imaging technology is an advanced detection and sensing technology, which takes the terahertz wave as the carrier or information source, takes the focal plane array as the main architecture, and has the advantages of all-weather, staring forward, high-resolution, real-time video imaging and so on. It is one of the main branches of terahertz research region. This paper first reviews the development history and the state-of-the-art of terahertz detection and sensing technology and several typical terahertz systems are highlighted. Then, the terahertz focal plane array imaging technology is reviewed, including low terahertz band (<1 THz) and high terahertz band (>1 THz) focal plane arrays. Finally, some consideration and suggestion are illustrated.