Abstract: There is provided a cooler which has a simple structure and stably exhibits a good cooling effect. A cooler includes: a container accommodating a working fluid; and a cooling member provided, in the container so as to be brought into contact with the working fluid and to face a heat generation element. The cooling member has a stacked structure including a first porous body provided on the heat generation element side and a second porous body provided on the working fluid side. The first porous body includes: a first working fluid supply part supplying the working fluid, by capillary action, to a contact part which is in contact with the heat generation element; and a first vapor discharge part discharging vapor generated in the contact part to the second porous body side. The second porous body includes: a second working fluid supply part supplying the working fluid to the first porous body; and a second vapor discharge part discharging the vapor discharged from the first porous body, into the working fluid.