In this study, Cs2AgBiBr6 double perovskite films, which is considered one of the alternative materials to organic‐inorganic Pb‐based perovskites in terms of toxicity and stability, are fabricated by gas quenching approach in ambient environment for the first time. Moreover, the study examines the effect of gas flowing rate on the solvent evaporation rate, crystallinity, morphology, and optical properties of the perovskite. The results indicate that the duration of color change from transparent to shiny yellow during gas quenching of Cs2AgBiBr6 films is influenced by the gas flowing rate, and this parameter has a notable impact on the properties of the films. In addition, incorporation of the gas quenched Cs2AgBiBr6 thin films in perovskite solar cells (PSCs) leads to 1.47% power conversion efficiency (PCE) with open‐circuit voltage (VOC) of 1.04 V, short‐circuit current density (JSC) of 2.11 mA cm‐2 and fill factor (FF) of 67.4%. Overall, this study provides a new approach to fabricate Cs2AgBiBr6 thin films in ambient atmosphere for potential optoelectronic applications.This article is protected by copyright. All rights reserved.