A refrigerator, comprising: a case with an inner case and an outer case and providing at least one storage compartment; at least one door (20, 30) that selectively opens and closes the case; a plurality of shelves (41, 51) disposed within the at least one storage compartment, that partitions the at least one storage compartment into a plurality of storage sections; a cold air duct provided in a space between the inner case and the outer case at a rear portion of the at least one storage compartment to supply cold air, wherein the cold air duct branches into two cold air ducts and communicates with a plurality of cold air supply holes of the inner case through which the cold air is supplied into the plurality of storage sections; a multi duct provided to be interposed between the two cold air ducts in a predetermined space formed between the inner case and the outer case, wherein the multi duct is forming an auxiliary sterilization passage independent from the cold air duct and has a plurality of outlets to draw the air exhausted from a filter module provided in the multi duct and communicating with at least one passing hole provided in the inner case to supply the filtered air to each of the plurality of storage sections; and the filter module comprises: a filter configured to filter air within the at least one storage compartment; a fan that draws air within the at least one storage compartment through the filter, and wherein the refrigerator comprises a control unit to control the operation of the filter module. a case with an inner case and an outer case and providing at least one storage compartment; at least one door (20, 30) that selectively opens and closes the case; a plurality of shelves (41, 51) disposed within the at least one storage compartment, that partitions the at least one storage compartment into a plurality of storage sections; a cold air duct provided in a space between the inner case and the outer case at a rear portion of the at least one storage compartment to supply cold air, wherein the cold air duct branches into two cold air ducts and communicates with a plurality of cold air supply holes of the inner case through which the cold air is supplied into the plurality of storage sections; a multi duct provided to be interposed between the two cold air ducts in a predetermined space formed between the inner case and the outer case, wherein the multi duct is forming an auxiliary sterilization passage independent from the cold air duct and has a plurality of outlets to draw the air exhausted from a filter module provided in the multi duct and communicating with at least one passing hole provided in the inner case to supply the filtered air to each of the plurality of storage sections; and the filter module comprises: a filter configured to filter air within the at least one storage compartment; a fan that draws air within the at least one storage compartment through the filter, and wherein the refrigerator comprises a control unit to control the operation of the filter module. a filter configured to filter air within the at least one storage compartment; a fan that draws air within the at least one storage compartment through the filter, and wherein the refrigerator comprises a control unit to control the operation of the filter module.