Provided is a non-invasive imaging apparatus of acquiring an image of a region of interest of an object, including: a laser supplying a laser beam a fiber bundle transmitting the laser beam to the region of interest of the object a transducer detecting an ultrasound signal output from the region of interest of the object corresponding to the laser beam supplied from the fiber bundle and generating and outputting an ultrasound detection signal and an ultrasound device generating and outputting a photoacoustic image by using the ultrasound detection signal output from the transducer, wherein the region of interest of the object is a gastrointestinal track of an animal, wherein the transducer detects the ultrasound signal of the gastrointestinal track of the animal into which a contrast agent is injected, and wherein the photoacoustic image is an image of the region of interest into which the contrast agent is injected.
