A heat transport device having a hydraulic fluid includes: an evaporating unit configured to receive heat from outside and gasify the hydraulic fluid into a gas; a condensing unit configured to liquefy the gas into the hydraulic fluid; and first and second fluid pipes respectively connected to the evaporating unit. The first and second fluid pipes forming an annular flow path with the evaporating unit and the condensing unit. The evaporating unit includes a first porous body which is permeated with the hydraulic fluid by capillary force, and a heat receiving unit configured to receive heat from outside. The heat receiving unit has an accommodation area where the first porous body moves in a first direction. The first fluid pipe is connected to one end side in the first direction of the accommodation area. The second fluid pipe is connected to the other end side of the accommodation area.