A method for leveling loads of distributed databases, comprising the steps of: counting loads of all servers in a distributed database system and a load proportion of each data slice on each server during a statistical period; ranking respective servers according to loads of the respective servers from the highest to the lowest, determining n top-ranked servers as high-load servers, and determining n bottom-ranked servers as low-load servers, where n is a positive integer; traversing the high-load servers and the low-load servers to perform the following operations, comprising: ranking respective data slices on an i-th ranked high-load server according to load proportions of the respective data slices on the i-th ranked high-load server from the highest to the lowest, and ranking respective data slices on an i-th inversely ranked low-load server according to load proportions of the respective data slices on the i-th inversely ranked low-load server from the highest to the lowest, where i is a positive integer, and i is less than or equal to n; and characterized in that the step of traversing further includes: determining a data slice on the i-th ranked high-load server as an i-th source data slice, determining a data slice on the i-th inversely ranked low-load server as an i-th target data slice, and in response to predetermining that an overall load proportion of the i-th inversely ranked low-load server among the respective servers is less than or equal to a predetermined first load proportion threshold after the i-th target data slice and the i-th source data slice are swapped, swapping the i-th source data slice and the i-th target data slice. counting loads of all servers in a distributed database system and a load proportion of each data slice on each server during a statistical period; ranking respective servers according to loads of the respective servers from the highest to the lowest, determining n top-ranked servers as high-load servers, and determining n bottom-ranked servers as low-load servers, where n is a positive integer; traversing the high-load servers and the low-load servers to perform the following operations, comprising: ranking respective data slices on an i-th ranked high-load server according to load proportions of the respective data slices on the i-th ranked high-load server from the highest to the lowest, and ranking respective data slices on an i-th inversely ranked low-load server according to load proportions of the respective data slices on the i-th inversely ranked low-load server from the highest to the lowest, where i is a positive integer, and i is less than or equal to n; and characterized in that the step of traversing further includes: determining a data slice on the i-th ranked high-load server as an i-th source data slice, determining a data slice on the i-th inversely ranked low-load server as an i-th target data slice, and in response to predetermining that an overall load proportion of the i-th inversely ranked low-load server among the respective servers is less than or equal to a predetermined first load proportion threshold after the i-th target data slice and the i-th source data slice are swapped, swapping the i-th source data slice and the i-th target data slice. ranking respective data slices on an i-th ranked high-load server according to load proportions of the respective data slices on the i-th ranked high-load server from the highest to the lowest, and ranking respective data slices on an i-th inversely ranked low-load server according to load proportions of the respective data slices on the i-th inversely ranked low-load server from the highest to the lowest, where i is a positive integer, and i is less than or equal to n; and characterized in that the step of traversing further includes: determining a data slice on the i-th ranked high-load server as an i-th source data slice, determining a data slice on the i-th inversely ranked low-load server as an i-th target data slice, and in response to predetermining that an overall load proportion of the i-th inversely ranked low-load server among the respective servers is less than or equal to a predetermined first load proportion threshold after the i-th target data slice and the i-th source data slice are swapped, swapping the i-th source data slice and the i-th target data slice.