The utility model provides an extend evaporation end area's heat pipe regenerative heat exchanger, including gravity heat pipe, the heat pipe is including evaporation end and condensation end, the evaporation end sets up in the heat accumulator, the heat accumulator sets up in the heat source, the condensation end sets up in the container of cold source, the cross -sectional area of heat accumulator is greater than the cross -sectional area of the container at cold source place. The utility model discloses a setting up the heat accumulator, can storing the heat in the heat source, the cross -sectional area through the heat accumulator is greater than the cross -sectional area of the container at cold source place moreover, and more heats can be stored moreover to the increase heat accumulator that can step forward and the heat transfer area of heat source, the further requirement of satisfying the heating.