The present invention provides an endoscopic optical coherence tomographic imaging probe and an imaging system thereof. The endoscopic optical coherence tomographic imaging probe comprises a single mode optical fiber and a beam turning member. A reflective surface is arranged between the end of the single mode optical fiber and the beam turning member. The beam turning component comprises a beam turning surface, and the included angle of the beam turning surface or its cut surface and the axial line of the singlemode optical fiber is an acute angle.A small part of the light of the light beam emitted by the singlemode optical fiberis reflected bythe reflective surface and returns to the original path to form a reference light, most of the light of the light beam emitted by the singlemode optical fiberis reflected by the beam turning surface and cast onasample structure to be measured, and the signal light returned from the sample structure passes through the beam turning member, is coupled into the single mode optical fiber of the probe, and then merges with the reference light to form an interference light signal. With the above technical scheme, a reference arm shares the light path with a sample arm, and the entire light path system is simpler, more compact, and more reliable; and the quality and stability of images are improved.