An object of the present invention is to provide a method and apparatus for clearing data in a cloud storage system. The method according to the present invention comprises the following steps: deleting meta information of a data slice corresponding to the file upon detecting that a user is deleting a file; wherein the method comprises the following steps: exporting all data slices to be processed when data needs to be cleared; by traversing each file in the meta information, determining each data slice that may be accessed through the meta information and thereby obtaining corresponding access data information; based on the access data information, determining the data to be cleared in said all data slices to perform data clearing operation for the data to be cleared. The present invention has the following advantages: avoiding likely deletion failure in the conventional manner of directly deleting the data information of the file, thereby reducing the storage space occupied by trash data and improving a resource utilization rate and a load level of the system.