The utility model discloses an office file cabinet relates to file cabinet technical field, including file cabinet, said file cabinet includes cabinet body shell, the bottom end of cabinet body shell inside is movably inserted with the storage drawer, the top end of cabinet body shell inside is provided with the storage cavity, the inside of storage cavity is provided with the spacing adjustment unit, the spacing adjustment unit is provided with the spacing adjustment unit, the spacing adjustment unit is provided with the spacing adjustment unit, and the spacing adjustment unit is provided with the spacing adjustment unit. And a space increasing unit is arranged on the right side of the cabinet body shell. Files needing to be stored can be conveniently placed by arranging the bearing plates, when the height of the files changes, the bearing plates can be pulled out to enable the clamping blocks on the two sides of the bearing plates to be correspondingly inserted into the clamping grooves, the distance between the two bearing plates can be conveniently adjusted, the application range is widened, the storage space can be enlarged by arranging the extension cabinet, and the storage space is saved. The extension cabinet provides an additional storage space, so that a user can conveniently store files in the extension area, when the extension cabinet is not used, the extension cabinet can be stored, the office space is not occupied, and the space utilization is optimized.