Optical projection tomography (OPT) technique, is a new mesoscopic (from millimeter to centimetre level) three-dimensional fluorescence imaging technique with the advantages of low cost, high speed, high resolution and large imaging depth, and is regarded as a hot spot in biomedical photonics research. We review the principles, research progress, and wide applications of OPT, and present the performances of different OPT techniques. The development of OPT technique is introduced from the view of improvement of OPT system (e.g. focal plane scanning, angular multiplexing, angular filtering), improvement of reconstruction algorithms, and incorporation of multi-dimensional fluorescence imaging techniques. Through the developments, OPT has been widely used in various research fields such as biomedical, morphology, histopathology, in vivo imaging, and fluorescence tracking.