Although organic-inorganic hybrid perovskites demonstrate promising potentials for photodetection, one great challenge still to be addressed is their relatively low responding speed (often at the magnitude order of ∼ms). Herein, a solution-processed photodetector based on polar two-dimensional (2D) multilayered hybrid perovskite crystal is fabricated, (C5H11NH3)2(CH3NH3)Pb2I7 (EMA, where C5H11NH3+ is n-pentylaminium), which exhibits an ultrafast responding time of ≈1.52 μs. This figure-of-merit is faster at least by 2–4 orders than other reported 2D organic-inorganic hybrid perovskite photodetectors. To the best of knowledge, this is the record-fast response-speed for lateral-type devices of 2D organic-inorganic hybrid perovskite. Such ultrafast responding can be attributed to the high crystallinity and quite low density of defects and traps. In addition, this device also presents a high photocurrent on/off ratio (>103) and extremely low dark current (≈10−10 A), indicating its potential applications for high-efficiency photodetectors. Our results pave the pathway toward ultrafast responding photodetection of 2D organic-inorganic hybrid perovskites.