The invention provides a data caching method for a distributed storage system, and the method comprises the steps: classifying data which is issued to each cache unit in the distributed storage systemand requires to be cached according to different dimensions, defining a label of each data type, and enabling the data to carry the label; Identifying a label of data requested to be stored, and obtaining a data type of the data requested to be stored; And caching the data according to the data type and a preset storage strategy. According to the method, the disk refreshing efficiency can be greatly improved, the use of cache resources is optimized, cache pollution is avoided, and the service quality of the whole distributed storage system is improved through the cache technology.