An imaging probe is suitable to be inserted into a tubular object so as to detect an interior image of the tubular object. The imaging probe includes a light source excitation assembly, an ultrasonic transducer and a receiver. The light source excitation assembly includes a pulsed laser, a first optical fiber and a cone-shaped reflecting member. The pulsed laser is suitable to generate a pulsed light energy. The cone-shaped reflecting member is suitable to reflect the pulsed light energy to let the pulsed light energy annularly irradiate the inner wall of the tubular object so as to produce a photoacoustic signal. The ultrasonic transducer is suitable to generate an ultrasonic signal. The ultrasonic signal annularly irradiates the inner wall of the tubular object so as to produce an ultrasonic echo signal. The receiver receives the photoacoustic signal and the ultrasonic echo signal.