A data replication method, comprising: obtaining differential data information corresponding to differential data that differentiates a primary volume from a secondary volume, wherein the differential data information comprises a storage address of the differential data that is located in the primary volume, and a differential data determining value of the differential data, and the differential data determining value comprises a data amount of the differential data or a ratio of the differential data amount of the differential data to a bandwidth for replication between the primary volume and the secondary volume; when it is determined that the differential data determining value is not less than a preset threshold, replicating the differential data from the primary volume to the secondary volume according to the storage address of the differential data that is located in the primary volume; and when it is determined that the differential data determining value is less than the preset threshold, taking a snapshot for the primary volume and replicating the differential data to the secondary volume according to the snapshot; wherein during a process in which the differential data is replicated from the primary volume to the secondary volume, the method further comprises: updating the differential data information by recording differential data information of differential data differentiating the primary volume from the secondary volume, and the recording differential data information of differential data is specifically: recording the differential data information of the differential data replicated from the primary volume to the secondary volume and by recording data information corresponding to the data sent by the system host to the primary volume; and no snapshot is taken for the primary volume until the differential data determining value decreases to be less than the threshold. obtaining differential data information corresponding to differential data that differentiates a primary volume from a secondary volume, wherein the differential data information comprises a storage address of the differential data that is located in the primary volume, and a differential data determining value of the differential data, and the differential data determining value comprises a data amount of the differential data or a ratio of the differential data amount of the differential data to a bandwidth for replication between the primary volume and the secondary volume; when it is determined that the differential data determining value is not less than a preset threshold, replicating the differential data from the primary volume to the secondary volume according to the storage address of the differential data that is located in the primary volume; and when it is determined that the differential data determining value is less than the preset threshold, taking a snapshot for the primary volume and replicating the differential data to the secondary volume according to the snapshot; wherein during a process in which the differential data is replicated from the primary volume to the secondary volume, the method further comprises: updating the differential data information by recording differential data information of differential data differentiating the primary volume from the secondary volume, and the recording differential data information of differential data is specifically: recording the differential data information of the differential data replicated from the primary volume to the secondary volume and by recording data information corresponding to the data sent by the system host to the primary volume; and no snapshot is taken for the primary volume until the differential data determining value decreases to be less than the threshold. updating the differential data information by recording differential data information of differential data differentiating the primary volume from the secondary volume, and the recording differential data information of differential data is specifically: recording the differential data information of the differential data replicated from the primary volume to the secondary volume and by recording data information corresponding to the data sent by the system host to the primary volume; and no snapshot is taken for the primary volume until the differential data determining value decreases to be less than the threshold.