CsPbBr 3 is a promising candidate for highly sensitive flat-panel X-ray detectors due to its excellent optoelectronic properties. Thus, a method of preparing thick CsPbBr 3 films (> 10 μm) over large areas (> 10× 10 cm 2) is required. Herein, we report the fabrication of thick CsPbBr 3 films using a scalable mist deposition method. In this method, the film thickness was controlled and up-scaled by the number of deposition cycles. The obtained CsPbBr 3 films were composed of highly (101)-oriented columnar crystals and had a high carrier mobility of 13 cm 2 V− 1 s− 1, which is comparable to that for single crystals.