To obtain an interleaver capable of rearranging data of a plurality of communication paths collectively, or a communication apparatus capable of sustaining a high throughput by averaging the communication conditions of respective communication paths.

The communication apparatus performing communication using N (an integer of 2 or above) communication paths comprises an interleaver 2 for rearranging a data sequence being transmitted to the N communication paths two-dimensionally in the time direction and the direction of frequency divided communication path, and a deinterleaver 5 for reproducing the original data sequence through rearragement processing reverse to that of the interleaver 2.