The application of photocatalytic technology in the field of water treatment can improve water quality safety and also alleviate the global energy and water shortage problems, which is a technology with wide application prospects. This paper firstly introduces the basic principle of photocatalytic technology and the characteristics of commonly used photocatalysts, reviews the research progress and development direction of photocatalytic technology in drinking water and wastewater treatment applications, focuses on the application of photocatalytic technology in drinking water for odor removal and disinfection, in dye wastewater, oil-containing wastewater, pharmaceutical wastewater, catalytic reduction of heavy metal ions, breeding wastewater, coking wastewater, and provides a reference for similar pollution Finally, the development of photocatalytic technology and photocatalysts is presented.