An acoustic wave detector that detects an acoustic wave from a subject, an optical fiber that guides light emitted from a light source to a probe body, and a light guide member that guides light from a light entrance end, which is optically coupled to the optical fiber, to a light exit end, which is located in the vicinity of the acoustic wave detector, are provided. The light guide member is secured in the probe body with a securing material provided at least partially around the light guide member. The conditional expression below is satisfied:sin−1(n2/n1)×(180°/π)<90°−θiwhere n1 is a refractive index of the light guide member, n2 is a refractive index of the securing material, and θi is a spread angle of incoming light from the optical fiber.
