The invention discloses a bag type dust removal device. The bag type dust removal device comprises a pretreatment device and a bag type dust remover, wherein the pretreatment device comprises a cyclone separating device and a first dust hopper; the first dust hopper is arranged at the bottom of the cyclone separating device; the bag type dust remover comprises an upper box body and a middle box body; a cold air system is arranged at the upper part of the upper box body; the middle box body is arranged at the bottom of the upper box body; an air inlet pipe and an air outlet pipe are arranged on the left side and the right side of the middle box body respectively; a filter bag assembly is arranged at the interior of the middle box body; a second dust hopper is arranged at the bottom of the middle box body; the cyclone separating device is connected to the air inlet pipe. The bag type dust removal device is high in dust removal efficiency and long in service life.