The invention specifically relates to a heat-transfer working medium and a preparation method thereof, and a method for heat transfer via a heat pipe, belonging to the technical field of heat transfer via heat pipes. The heat-transfer working medium provided by the invention comprises a first alcohol compound, a fluid working medium and water. The surface tension of the heat-transfer working medium decreases with increase of temperature, drops to a minimum value at a certain thermal and then gradually increases with increase of temperature; the heat-transfer working medium has a self-moistening characteristic and can spontaneously wet the dryout part of a heat pipe, effectively delay occurrence of the phenomenon of dryout and enhances heat transfer efficiency; and the heat-transfer working medium has excellent performance and can be used for improving the heat transfer performance of microelectronic heat pipes and overcoming problems in heat radiation of microelectronic chips.