A frame-type air purifier includes a purifier housing, a main frame and an image board. The purifier housing has a back plate and a front plate configured opposite to each other. The back plate has a wall positioner configured thereon. The front plate includes a first quick-demounting member configured thereon. The main frame has a central hollow and a second quick-demounting member configured thereon. The image board includes a baseboard and an imaging sheet configured on the baseboard, wherein the baseboard has a third quick-demounting member configured thereon. The first quick-demounting member of the purifier housing selectively assembles with the second quick-demounting member of the main frame correspondingly, or selectively assembles with the third quick-demounting member of the image board correspondingly.