Bismuth oxyhalides (BiOX, X = Cl, Br, and I) have sparked a lot of interest among researchers due to their special layered structures, optical, and electronic properties. Under visible light irradiation, bismuth-based photocatalysts have shown efficient photocatalytic activities for the removal of harmful effluents, water splitting, antibacterial activity, and sensor studies. However, the photocatalytic performance of BiOX is limited when it comes to the practical application due to their band structures and fast electron-hole recombination. Various modifications have been explored to enhance the photocatalytic performance towards the visible light spectrum such as doping with metal or non-metal elements and heterojunction design. This review summarized the reported studies on the synthesis methods of preparing bismuth oxyhalides, modifications of bismuth oxyhalides and their photocatalysis, hydrogen production, antibacterial studies, and their sensing properties.