To provide a lightweight and compact vehicular pump device with a simple structure, which can expand utilization range of pressure air, rarely requires maintenance and inspection work, and can maintain a steam separating function of lead-in air over an extended period thanks to high durability.

In this vehicular pump device, a pump part 4, which is operated by relative rotation between a stationary shaft 1 and a rotating part 3 and takes and pressurizes ambient air, is placed in a wheel hub part 2. In a valve passage 33 functioning as an air intake part, an air-permeable sheet 35 is positioned. Thanks to this, the pump itself is compactly housed inside the existing components, which makes the pump device lightweight, simple, and useful for light vehicles, such as bicycles. Meanwhile, when the pump device is installed inside a hub drum 3 and the like, a centrifugal force has fewer effects on the pump device, and wheel balance is unnecessary. Moreover, the high durability of the pump device makes it possible to maintain a steam separating function of lead-in air over an extended period and to ensure higher maintenance-free performance.