The sectioning capability of the endoscope-based speckle quasi-confocal system (EBSQCS) is studied. Based on the theory of speckle quasi-confocal microscope (SQCM), the influence of endoscope on the discipline of speckle quasi-confocal microscope speckle fluctuation is discussed, and analytical expression is derived to describe the relationship between optical structure of endoscope and the axial resolution of Endoscope-based speckle quasi-confocal system. The axial resolution curve is also obtained by experiment of Endoscope-based speckle quasi-confocal system with a fiber bundle. The full width at half maximum (FWHM) of Endoscope-based speckle quasi-confocal system resolution curve is 2.3 times of that of speckle quasi-confocal microscope when the endoscope has a magnification of 4 times and fiber diameter of 5 μm, which is in accordance with the theory. The experimental result shows that eEndoscope-based speckle quasi-confocal system has the quality of axial optical sectioning.