The disclosure discloses a method of supporting arbitrary replacement of multiple data units, which includes: configuring patterns for arbitrary position replacement of N data units; and during a process of data unit replacement, performing a replacement operation on the N data units according to the configured patterns. The disclosure further discloses a device of supporting arbitrary replacement of multiple data units. By means of the method and device, an occupied area of a data unit replacement circuit in a chip can be decreased, and power consumption can be reduced.