A refrigerator, comprising: a main body having a storage room formed therein, wherein the main body includes an inner casing that defines the storage room; a cool air supply path provided in the main body and configured to supply cool air to the storage room; a cool air supply fan configured to supply the cool air to the storage room through the cool air supply path; a cool air circulation path configured to circulate air in the storage room therethrough; a cool air suction hole formed at the inner casing to guide air from the storage room into the circulation path; a filter module provided in the cool air circulation path and configured to filter cool air to be conveyed to the storage room, wherein the filter module comprises: a metal photocatalyst filter including photocatalysts and an ultraviolet LED module which radiates UV rays to the metal photocatalyst filter, wherein the filter module includes a filter casing having an air suction hole and air outlets and the filter module includes a filter casing cover, wherein the filter casing extends longitudinally in the air flow direction, wherein the filter casing cover is coupled to the filter casing to cover a part of the air suction hole and separated from the air suction hole such that air in the storage room is drawn into the air suction hole through a gap between the filter casing cover and the filter casing, wherein the metal photocatalyst filter and the UV LED module are sequentially disposed in an air flow direction of the cool air to be supplied to the storage room, wherein the photocatalysts of the metal photocatalyst filter are made of one selected from a group consisting of ZnTiO 2, CuTiO 2, AgTiO 2, and FeTiO 2 coated on a filter base, wherein a cool air circulation fan is installed adjacent to the filter module, and the cool air circulation fan has a smaller size than the cool air suction hole such that the cool air circulation fan can be drawn out through the cool air suction hole. a main body having a storage room formed therein, wherein the main body includes an inner casing that defines the storage room; a cool air supply path provided in the main body and configured to supply cool air to the storage room; a cool air supply fan configured to supply the cool air to the storage room through the cool air supply path; a cool air circulation path configured to circulate air in the storage room therethrough; a cool air suction hole formed at the inner casing to guide air from the storage room into the circulation path; a filter module provided in the cool air circulation path and configured to filter cool air to be conveyed to the storage room, wherein the filter module comprises: a metal photocatalyst filter including photocatalysts and an ultraviolet LED module which radiates UV rays to the metal photocatalyst filter, wherein the filter module includes a filter casing having an air suction hole and air outlets and the filter module includes a filter casing cover, wherein the filter casing extends longitudinally in the air flow direction, wherein the filter casing cover is coupled to the filter casing to cover a part of the air suction hole and separated from the air suction hole such that air in the storage room is drawn into the air suction hole through a gap between the filter casing cover and the filter casing, wherein the metal photocatalyst filter and the UV LED module are sequentially disposed in an air flow direction of the cool air to be supplied to the storage room, wherein the photocatalysts of the metal photocatalyst filter are made of one selected from a group consisting of ZnTiO 2, CuTiO 2, AgTiO 2, and FeTiO 2 coated on a filter base, wherein a cool air circulation fan is installed adjacent to the filter module, and the cool air circulation fan has a smaller size than the cool air suction hole such that the cool air circulation fan can be drawn out through the cool air suction hole. a metal photocatalyst filter including photocatalysts and an ultraviolet LED module which radiates UV rays to the metal photocatalyst filter, wherein the filter module includes a filter casing having an air suction hole and air outlets and the filter module includes a filter casing cover, wherein the filter casing extends longitudinally in the air flow direction, wherein the filter casing cover is coupled to the filter casing to cover a part of the air suction hole and separated from the air suction hole such that air in the storage room is drawn into the air suction hole through a gap between the filter casing cover and the filter casing, wherein the metal photocatalyst filter and the UV LED module are sequentially disposed in an air flow direction of the cool air to be supplied to the storage room, wherein the photocatalysts of the metal photocatalyst filter are made of one selected from a group consisting of ZnTiO 2, CuTiO 2, AgTiO 2, and FeTiO 2 coated on a filter base, wherein a cool air circulation fan is installed adjacent to the filter module, and the cool air circulation fan has a smaller size than the cool air suction hole such that the cool air circulation fan can be drawn out through the cool air suction hole.