The present invention relates to an apparatus and method for managing files in a distributed storage system. The apparatus and method for managing a file in a distributed storage system according to the present invention counts the number of inquiries on a file requested by a client; selects the file as a hot file if the number of inquiries counted in a certain counting period is larger than a hot file selection threshold value; and increases the number of copies of the file selected as a hot file or stores the file selected as a hot file in a storage device having a relatively good performance.