Described herein are heat-sensitive sublimation transfer cyan dyes represented by the following formula (I): ( I ) wherein R1 represents a hydrogen atom, an alkyl group, an alkoxyl group, an alkylcarbonylamino group, a formylamino group or a halogen atom, R2 and R3 represent an alkyl group, an alkenyl group, an alkoxyalkyl group, an aralkyl group, an aryl group, a halogenoalkyl group or a cyanoalkyl group or are coupled together to form a ring, and X represents any one of the following groups: , and Heat-sensitive sublimation transfer sheets containing one or more dyes selected from the group of the above dyes are also described.