An acoustic wave imaging apparatus has a phase aligning unit, which aligns phases of received signals obtained by a plurality of acoustic wave receiving elements. A complex signal acquiring unit generates complex signals out of the phase aligned received signals, and a correlation matrix calculating unit calculates a correlation matrix of the complex signals. An electric power calculating unit calculates constrained minimum power of the received signals, using the correlation matrix and a predetermined constraint vector. The correlation matrix calculating unit calculates the correlation matrix at a predetermined cycle, and sequentially outputs the calculated correlation matrix to the electric power calculating unit at a predetermined cycle, and the electric power calculating unit calculates a plurality of constrained minimum powers in parallel using the calculated correlation matrices, the plurality of constrained minimum powers corresponding to the correlation matrices respectively.