Boron nitride (BN) presented enormous potential in the fabrication of novel membranes with superior separation efficiency. Researchers try to produce membranes with high solvent permeability and good rejection performance in industrial applications. In this review, the recent progress in the fabrication of BN-based membranes with different fabrication techniques and various applications is reviewed. Representative studies on applying BN-based membranes in gas separation, proton exchange, electrodialysis, and water filtration membranes to develop their performance and stability, induce antifouling characteristics, and decline the trade-off between selectivity and permeability, together with the explanation of their mechanisms, are discussed. Moreover, various methods of synthesis of BN allotropes are introduced. In addition, a brief review of simulation studies (molecular dynamic and density function theory) on theoretical studies of BN nanosheet membranes was performed. The authors hope that this review will arouse the active interest of many researchers in the further development of the BNs application in membrane science and technology.