In recent years, organic photomultiplication photodetectors with external quantum efficiency far exceeding 100% have drawn extensive research attention. This paper firstly presents the typical structures of organic photomultiplication photodetectors and their working mechanisms. Organic photomultiplication photodetectors can be divided into two types depending on the material properties of active layers. One is the small organic molecule photomultiplication photodetector and the other is the polymer photomultiplication photodetector. This paper reviews the progress of these two different types of organic photomultiplication photodetectors. Then, we introduce some important developments in optimizing quantum efficiency, dark current, response speed and spectral performance of organic photomultiplication photodetectors in detail. Later, we briefly show some different explanations proposed by researchers for explaining the working mechanism of organic photomultiplication photodetectors. Finally, we summarize the paper and provide the prospect of organic photomultiplication photodetectors.