In an evaporator that constitutes part of a vehicular air conditioning apparatus, first fins having louvers therein are arranged between first and second tubes. Together therewith, a second fin, which does not have any louvers therein, is provided at a boundary portion between a first cooling section, which faces toward a first front passage through which air from a first blower unit flows, and a second cooling section, which faces toward a first rear passage through which air from a second blower unit flows. In addition, air is supplied to the interior of a casing from the first blower unit and is cooled by the first cooling section, which is partitioned by the second fin, whereas air supplied from the second blower unit passes through the second cooling section, which is partitioned from the first cooling section by the second fin.