In　the　past　few　decades,　the　applications　of　terahertz　(THz)　spectroscopy　and　imaging　technology　have　seen　significant　developments　in　the　fields　of　biology,　medical　diagnosis,　food　safety,　and　nondestructive　testing.　Label-free　diagnosis　of　malignant　tumours　has　been　obtained　and　also　achieved　significant　development　in　THz　biomedical　imaging.　This　review　mainly　presents　the　research　status　and　prospects　of　several　common　continuous-wave　(CW)　THz　medical　imaging　systems　and　applications　of　THz　medical　imaging　in　biological　tissues.　Here,　we　first　introduce　the　properties　of　THz　waves　and　how　these　properties　play　a　role　in　biomedical　imaging.　Then,　we　analyse　both　the　advantages　and　disadvantages　of　the　CW　THz　imaging　methods　and　the　progress　of　these　methods　in　THz　biomedical　imaging　in　recent　ten　years.　Finally,　we　summarise　the　obstacles　in　the　way　of　the　application　of　THz　bio-imaging　application　technology　in　clinical　detection,　which　need　to　be　investigated　and　overcome　in　the　future.