As a two-dimensional (2D) inorganic molecular van der Waals crystal, Sb2O3 has been widely recognized as an excellent dielectric and encapsulation material due to its wide bandgap, high dielectric constant (κ), and remarkably high air stability. Considering the significance and potential application of Sb2O3 in future electronic devices, it is valuable to summarize its recent advancements. In this review, we present the latest progress on 2D Sb2O3 flakes and films, encompassing synthesis methods, physical properties, and device applications. First, preparation strategies such as chemical vapor deposition, vertical physical vapor deposition, thermal evaporation deposition, liquid metal synthesis, and atomic layer deposition growth routes are highlighted. Subsequently, the mechanical properties and the phase transition mechanisms of 2D Sb2O3 are presented. Moreover, device applications, including encapsulation layer, photodetector, and gate dielectric, are demonstrated. Finally, we outline the future challenges and research priorities of 2D Sb2O3 materials.