A thermosensitive recording sheet having a thermosensitive color developing layer containing a basic leuco dye and an organic color developer, said layer containing a polyphenyl ester compound of the general formula
wherein R 1 and R 2 , independently from each other, represent an alkyl group, a cycloalkyl group, or an aryl, aralkyl or aryloxyalkyl group which may have at least one substituent selected from the class consisting of halogen atoms, nitro groups, hydroxyl groups, lower alkyl groups and lower alkoxy groups.