The invention provides a data processing method and device. The method comprises the following steps: when a target disk is in failure in an array reconstruction process, inserting a new disk into an array to replace the target disk of responding to data read-write, and updating stripe attributes corresponding to the new array, wherein data on the new disk in an old data stripe is invalid data, data on the new disk in a new data stripe is valid data, the old data stripe and the new data stripe are stripes where the new disk is positioned, the old data stripe is the stripe where data, written in before the new disk is added, is positioned and the new data stripe is the stripe where data, written in after the new disk is added, is positioned; when a data reading request is received, carrying out data reading according to stripe attributes corresponding to the array. By adopting the method and device provided by the invention, under the circumstance that a large amount of redundant backup space or redundant equipment is not required to be reserved, normal read-write of new data can be realized, that old data is read as far as possible is realized and resource consumption of storage space is reduced.