Ratiometric sensing nanoprobes derivatized from luminescent dyes show great application in a nano or micro system as well as in a sensing material.Nowadays,a ratiometric nano sensing system has attracted a wide variety of attentions.In this review,the meaning of measuring oxygen concentration was introduced and the determination approaches for O2 was discussed.The research progress of nanosensors for O2 based on ratiometric fluorescence including their preparation,characteristics and applications,was systematically reviewed.