The time response relation of central position drift of FBG temperature sensor reflection wavelength is theoretically analyzed,influence of material,heat exchange coefficient,cladding and other factors on FBG temperature and time response speed is discussed.The temperature and time response characteristic of bare FBG in medium as well as the temperature and time response characteristic of FBG in cladding are respectively verified through experiment.Through experimental verification,the hysteresis quality of FBG sensor reflection wavelength central position drifts is greatly related to fiber optic materials,optical surface area and surface thermal conductance h.The larger the surface coefficient is,the shorter the retardation time of reflection wavelength central position drifts will be.The change rule conforms to the theoretical analysis results.