The nature-inspired, flexible, and reentrant liquid-superrepellent surfaces have garnered significant attention due to their superomniphobic performance against low-surface-tension liquids. In this paper, we proposed a proximity lithography method that enables the fabrication of both singly (single-exposure) and doubly (double-exposure) reentrant microstructures without the need for double-sided exposure. This method allows for large-area manufacturing and efficient production of reentrant microstructures by precisely designing feature sizes on a photomask with coaxial circular apertures and rings, the number of exposures and adjusting the proximity exposure distance. A theoretical model has been developed to predict the sizes of reentrant microstructures based on the three-dimensional light intensity distribution in proximity lithography. The flexible and reentrant microstructures were achieved by replicating the SU-8 master through surface modification and adjusting the Young's modulus of the transfer material. These flexible surfaces exhibit exceptional superomniphobic performance, showcasing its potential applications in self-cleaning, membrane distillation, and digital microfluidics.