An array antenna is provided. The array antenna includes at least one pair of interleaved TR antenna arrays in a continuous arraying direction, where the TX arrays and RX arrays of two adjacent TR antenna arrays are interleaved. This can effectively rectify discontinuousness of TX arrays and RX arrays in a discontinuous arraying direction in the prior art, and thereby reduce grating lobes or side lobes caused by discontinuous TX arrays and discontinuous RX arrays in an array antenna, so that performance of the array antenna improves.