A power storage device includes: a power storage module; a housing case having a housing space formed therein and configured to house the power storage module in the housing space; a cooler arranged in the housing case and configured to cool air sent toward the power storage module; a storage portion configured to store condensation water generated as a result of cooling by the cooler; and an air permeable film configured to allow a vapor generated from the condensation water stored in the storage portion to pass therethrough. The storage portion and the air permeable film are provided in a separated space separated from the housing space. The vapor passes through the separated space and reaches the air permeable film.