In this work, one-step coating of CsPbBr₃ thin films using the mist deposition method is demonstrated. The CsPbBr₃ layer is composed of large grains with an average size of approximately 1.4 μm, and it fully covers the substrate surface, unlike the layers prepared by conventional one-step spin-coating methods, so that efficient carrier transport is realized. Carbon-based CsPbBr₃ perovskite solar cells (PSCs) fabricated using the mist deposition method exhibit a stabilized power conversion efficiency of 7.7%, which is a record value for carbon-based CsPbBr₃ PSCs prepared via a one-step solution process.