Thiochrome monophosphate (ThcMP), thiochrome diphosphate (ThcDP) and thiochrome triphosphate (ThcTP) were synthesized and their fluorescent properties were investigated. In strong alkaline solution (pH 13〜14), maxima in the excitation wavelength of these thiochrome esters are located at 372 nm and emission maximum of the esters are as follows; thiochrome: 457 nm, ThcMP: 453 nm, ThcDP: 450 nm and ThcTP: 449 nm. Relative follows; thiochrome : ThcMP : ThcDP : ThcTP=1 : 1.27 : 1.57 : 1.75. Fluorescence intensity of thiochrome showed maximum at pH 8〜10, whereas, fluorescence intensities of ThcMP, ThcDP and ThcTP increased in proportion to the increase in pH value. The fluorescent properties of products from thiamine, TMP, TDP and TTP by cyanogen bromide-NaOH reaction were similar to those of synthesized thiochrome esters.