Terahertz technology is continually evolving and much progress has been made in recent years. Many new applications are being discovered and new ways to implement terahertz imaging investigated. In this review, we limit our discussion to biomedical applications of terahertz imaging such as cancer detection, genetic sensing and molecular spectroscopy. Our discussion of the development of new terahertz techniques is also focused on those that may accelerate the progress of terahertz imaging and spectroscopy in biomedicine.