An air cell including a strip body and a waterproof air-permeable cover is provided. The strip body has an air hole, a upper surface, and a side surface integrated with the upper surface. The upper surface is constituted by a air-permeable region and a airproof region. The side surface and the airproof region are made of airproof material, and the air-permeable region is constituted by a opening. The waterproof air-permeable cover is disposed at the strip body and covers the opening. When the air cell is in a use state due to air inflation through the air hole, part of gas in the strip body flows out of the air cell through the waterproof air-permeable cover. In addition, an air mattress and an air mattress system including the air cell is also provided.
