This study investigated the feasibility of photoacoustic(PA)imaging of bone and characterization of bone fea-tures.By conducting the experiments on bovine femoral heads ex vivo,the light and ultrasonic penetration in bones was studied,together with the depth of PA imaging and measurement in bones.Then,the possibility of three-dimensional(3D)PA imaging of bones by raster scanning of the focusing transducer was studied.The micro-computerized tomography images of the bovine ribs with and without ethylenediaminetetraacetic acid(EDTA)treatment indicated that the 3D PA images could present the changes of bone microstructure resulting from the EDTA treatment.By using PA spectral analysis,the bone samples with and without the treatment of EDTA solution can be distinguished,and the microstructures can be characterized.This study was based on the bovine bone whose size is comparable to human bones,suggesting that PA technology can be used as a novel bone diagnostic technique.