A frame-type air purifier includes a purifier housing and a front cover. The purifier housing includes a rear plate and a circumferential plate. The circumferential plate surrounds an outer periphery of the rear plate and forms a basin-shaped space. The basin-shaped space is divided into an open chamber and a close chamber. The open chamber includes a front opening. The close chamber includes an air inlet. The close chamber receives a purifier body. The front cover includes a front plate and a side frame. The side frame surrounds an outer periphery of the front plate and extends towards the rear plate. The front cover covers the front opening without contacting. The front plate and the circumferential plate are spaced by a longitudinal spacing. The side frame and the circumferential plate are spaced by a lateral spacing. The longitudinal spacing and the lateral spacing form an L-shaped air inlet channel.