A DC air pump is provided with an accommodating space in an integrally formed box body, and an opening communicating with the accommodating space is arranged on the bottom side, and a venting module and a switch are arranged in the accommodating space of the box body The pull-type bottom cover is adapted to receive the battery pack, and the bottom cover can electrically connect the battery pack to the switch group in the casing when the opening is closed on the bottom side of the casing, The switch group is electrically opened and closed； thereby, the box body formed by one of the openings on the bottom side can effectively prevent the water from splashing into the box from above and can pull the bottom cover It is easy to replace the battery pack, thereby achieving the effect of effectively improving the waterproof effect and being easy to use.一種直流打氣泵，其係於一體成型之盒體內設有容置空間，底側則設有與該容置空間相通之開口，該盒體之容置空間內係裝設有打氣模組及開關組，一抽拉式的底蓋係可供承置電池組，該底蓋並於蓋合該盒體底側之開口時，可使該電池組電性連結於盒體內之開關組，而可由該開關組作電性的啟閉控制；藉此，利用僅於底側具有開口之一體成型的盒體，即可有效的防止水液自上方噴濺而滲入盒體內，並且可抽拉底蓋而易於更換電池組，進而達到有效提升防水效果及便於使用之效益。
