Abstract: The present invention relates to a two-photon fluorescent probe, more particularly a two-photon fluorescent probe represented by Formula 1, a method for preparing same and a method for imaging thiols in mitochondria using same. The two-photon fluorescent probe according to the present invention, having two probes introduced in one molecule, can selectively dye mitochondria and emit intense fluorescence by reacting with thiols. Accordingly, it can be used to image the distribution and activation of thiols in a living cell or an intact living tissue.