An effective cooling system is provided by the configuration including: a blower; a first rectifier comprising a first opening that lets a first diversion pass through and a second opening that lets a second diversion divided from airflow pass through downstream a first electronic device; a mixing room that is arranged at a downstream portion of the first rectifier and that mixes the first diversion having passed through the first opening and the second diversion having passed through the second opening; and a second rectifier that is arranged at a downstream portion of the mixing room and includes a third opening and a fourth opening, a mixed airflow of the first diversion and the second diversion passing through the third opening and the fourth opening.