The invention relates to a novel fluorane compound and a preparation method thereof, belongs to the technical field of thermosensitive dyes, and is used for solving at least one of the problems of higher color development temperature, non-bright color after color development, low color density, complex synthesis method, low purity and the like of pink dyes in the prior art. The novel fluorane compound which has a conjugated structure with the parent
nucleus is synthesized, the color development temperature of the compound is relatively low, color development can be performed when the temperature reaches about 70 DEG C, the color development capability of the fluorane parent
nucleus is enhanced, the fluorane parent
nucleus is pink in color development, the color is brighter after color development, and the color density value is higher.