An air cleaner comprising: an air cleaning module including a base placeable on a ground, a filter frame disposed on the base and forming a mounting space for a cylindrical filter, a fan housing accommodating a fan therein, an air guide coupled to the upper side of the fan housing, and a discharge guide forming an outer appearance of an upper end portion of the air cleaning module; and a case forming an outer appearance of the air cleaning module in a cylindrical shape; wherein the case includes: a first part and a second part in a same shape, a separation portion forming end portions of the first part and the second part, and a suction inlet having a plurality of suction portions (102a, 102b) wherein the first part and the second part are detachably coupled to each other when the two parts (101a, 101b) of the case are assembled to the air cleaning module, the separation portion is formed in a vertical direction along the end portions of the first part and the second part of the case, the fan housing is provided inside the case, and the filter frame with the cylindrical filter is provided under the fan housing and inside the case, characterized in that an outer surface of the fan housing and an inner surface of the case are spaced apart from each other to form a housing suction flow path for guiding air sucked into the cylindrical filter. an air cleaning module including a base placeable on a ground, a filter frame disposed on the base and forming a mounting space for a cylindrical filter, a fan housing accommodating a fan therein, an air guide coupled to the upper side of the fan housing, and a discharge guide forming an outer appearance of an upper end portion of the air cleaning module; and a base placeable on a ground, a filter frame disposed on the base and forming a mounting space for a cylindrical filter, a fan housing accommodating a fan therein, an air guide coupled to the upper side of the fan housing, and a discharge guide forming an outer appearance of an upper end portion of the air cleaning module; and a case forming an outer appearance of the air cleaning module in a cylindrical shape; wherein the case includes: a first part and a second part in a same shape, a separation portion forming end portions of the first part and the second part, and a suction inlet having a plurality of suction portions (102a, 102b) wherein the first part and the second part are detachably coupled to each other when the two parts (101a, 101b) of the case are assembled to the air cleaning module, the separation portion is formed in a vertical direction along the end portions of the first part and the second part of the case, the fan housing is provided inside the case, and the filter frame with the cylindrical filter is provided under the fan housing and inside the case, characterized in that an outer surface of the fan housing and an inner surface of the case a first part and a second part in a same shape, a separation portion forming end portions of the first part and the second part, and a suction inlet having a plurality of suction portions (102a, 102b) wherein the first part and the second part are detachably coupled to each other when the two parts (101a, 101b) of the case are assembled to the air cleaning module, the separation portion is formed in a vertical direction along the end portions of the first part and the second part of the case, the fan housing is provided inside the case, and the filter frame with the cylindrical filter is provided under the fan housing and inside the case, characterized in that an outer surface of the fan housing and an inner surface of the case are spaced apart from each other to form a housing suction flow path for guiding air sucked into the cylindrical filter.