An air breather chamber structure includes: a first breather chamber provided to a housing receiving a transmission; and a second breather chamber provided to an upper portion of the housing in a gravity direction, the first introduction hole being positioned on the first side of the imaginary surface, the second introduction hole being positioned on the second side of the imaginary surface, the atmosphere communication hole being positioned on the first side of the imaginary surface, the discharge hole being positioned on the second side of the imaginary surface, the first introduction hole and the discharge hole being positioned below the second introduction hole in the gravity direction, and the atmosphere communication hole being positioned above the second introduction hole in the gravity direction.