[Objective]To provide a photoacoustic imaging method that enables photoacoustic images to be displayed at high speed.[Constitution]A photoacoustic imaging method scans a subject with a light beam output by a laser unit (13), for example, detects acoustic waves generated within the subject due to the scanning of light to obtain acoustic wave detected signals, and generates volume data that represent three dimensional photoacoustic images of the subject based on the acoustic wave detected signals. A projection image generating section (60) generates photoacoustic projection images projected in the direction of irradiation depth of the light and generates photoacoustic tomographic images of the subject related to planes that extend in the direction of irradiation depth of the light, prior to the volume data being generated and concurrently with the scanning of the light. The photoacoustic tomographic images and the photoacoustic projection images are displayed by an image display means (14).
