The invention relates to a replacement method for a converter integral flue. The method comprises the following steps that S1) a lifting hook of a truck-mounted crane is placed right above the position close to a converter body (28) and a water-cooled beam (1), different winches are arranged on different operation platforms, and corresponding guide sliding blocks and pulley blocks are placed and installed; S2) an old moving section flue body is disassembled, and the old moving section flue body is conveyed to a garbage area through a charging bay travelling crane (9); S3) a new moving sectionflue body (5) is installed for replacing the old one through a high-bay travelling crane (10) and a transition carriage (2); S4) then an old fixed first-section flue body, an old fixed second-sectionflue body and an old fixed tail-section flue body are sequentially disassembled; S5) a new fixed tail-section flue body (8), a new fixed second-section flue body (7) and a new fixed first-section fluebody (6) are sequentially installed for replacing the old ones, then the new moving section flue body is moved, and the replacement of the whole flue is completed; and S6) pressurizing and water testing are carried out on the whole flue so as to detect whether the joint between each flue body and an external water pipe leaks or not.