CsPbCl3-based inorganic perovskite ultraviolet photodetectors (UV-PDs) have a great promise for the wide application prospects due to the desirably UVmatched energy band and the excellent intrinsic optoelectronic properties. However, the traditional high-temperature Bridgman method (near 600 °C) and complexly time-consuming vapor preparation (several days) of highquality CsPbCl3 crystals have badly restricted its commercial applications to date. Herein, an antisolvent-induced crystallization kinetics (ACK) strategy is demonstrated for the quick lower-temperature fabrication (50 °C, tens of minutes) of excellent continuous highly crystalline CsPbCl3 microcrystal films (MCFs) with low trap density (1.42 × 1012 cm?3). Further, the as-developed CsPbCl3 MCF-based UV-PDs present a high detectivity of 5.6 × 1012 Jones, a superior responsivity of 2.11 A W?1, and robust stability. Evidently, this work provides a rapid and simple method to prepare high-quality perovskite MCFs, greatly promoting the commercial development of perovskite-based

photodetectors.