To provide a heat-sensitive recording body excellent in the fastness of a developed color image at elevated temperature under highly humid conditions.

In this heat-sensitive recording body, which is formed by providing a recording layer containing colorless or light-colored basic dye and coloring agent, the recording layer contains at least one king of fluoran compound represented by the formula as the basic dye, in which R1 represents hydrogen atom or 1-6C alkyl group, R2 represents hydrogen atom, 1-6C alkyl group, cycloalkyl group or phenyl group, R3 represents -COR5, -COOR6, CH2R7, CH2.CH =CH2 or 1-4C alkyl group, R5 represents hydrogen atom, 1-4C alkyl group or phenyl group, R6 represents 1-4C alkyl group, R7 represents phenyl group and R represents 1-4C alkyl group or phenyl group.