The invention discloses an inert anode for a system for purifying flue gases by utilizing molten salts. The inert anode is sequentially provided with a matrix, a diffusion barrier transition layer and a precious metal protective layer from inside to outside; the matrix is made of any one material selected from nickel, titanium and molybdenum metals as well as alloys taking the metals as main components; and the precious metal protective layer is made of any one material selected from platinum, iridium and ruthenium metals as well as alloys taking the metals as main components. The diffusion barrier transition layer is made of any one material selected from titanium carbide, titanium nitride, tantalum nitride and zirconium nitride. The inert anode disclosed by the invention can resist to the erosion of sulfates, nitrates, chlorates and carbonates and has the characteristics of high oxygen evolution capacity, long working life, high efficiency, relatively low price, simple manufacturing process, excellent mechanical strength, convenience in connection and installation and production amplification capability.