To inhibit the occurrence of dew condensation by securing an airway in an exterior wall and discharging moisture to the outside by the use of the airway.

This ventilation wall structure includes: a skeleton 1 which defines indoor and outdoor sides of a building; waterproof paper 2 which is spread on the skeleton 1; a lath 3 which is connected to the skeleton 1 via the waterproof paper 2; and mortar 4 which is applied to the lath 3. In the ventilation wall structure, the lath 3 comprises a body 3a which faces the waterproof paper 2 with a gap between while having a lath mesh allowing the application of the mortar 4, and a protrusion 3b which is formed integrally with the body 3a and connected to the skeleton 1 while making a tip abut on the waterproof paper 2; and the airway S is formed between the waterproof paper 2 and the mortar 4 applied to the outdoor side surface of the body 3a of the lath 3.