Because of its high resolution,inherent optical sectioning and deep optical penetration,two-photon microscopy has been regarded as an excellent method for noninvasive detection. A potential clinical application of these microscopes based on optical fibers is their endoscopic use for optical biopsy of inner organs or brain of awake,behaving animals. The technology to build miniaturized fluorescence microendoscopes was reviewed. The different fibers used in two-photon microendoscope to propagate the excited laser and collect the fluorescence signal such as single mode,multi-mode and photonic crystal fibers were contrasted. Various scanning mode and system design were introduced. The research development and potential application were also discussed.