The research progress of solid solution materials in the field of photocatalysis was introduced. The synthesis methods of solid solution photocatalytic materials are comprehensively expounded, and the modification strategies of solid solution photocatalysts are analyzed and discussed. This paper systematically summarizes the characteristics and development of the main catalytic systems of solid solution materials, and explored the application of first-principles calculations in the photocatalysis of solid solution materials in combination with practical research. Subsequently, the main application progress of photocatalysis of solid solution materials in the fields of environmental remediation and energy conversion was introduced. Finally, the current challenges, development directions and prospects are prospected.