Abstract: Disclosed is ultrafast photographing apparatus based on polarization-time mapping, which can obtain spatiotemporal (x, y, t) information of a dynamic scene by means of single exposure. The apparatus includes an active illumination system, a synchronous control system, a data acquisition system, and a data reconstruction system. Firstly, illumination light is generated by the active illumination system to irradiate on a dynamic scene; the synchronous control system is configured to control the single exposure of a camera; the data acquisition system is configured to acquire a two-dimensional image containing sixteen frames of spatiotemporal aliasing by means of polarization modulation and polarization filtering; and the data reconstruction system is configured to reconstruct the acquired image by using an iterative Tikhonov regularization algorithm, and finally to restore sixteen frames of original dynamic scenes with time series information.