The invention relates to an air water-collecting sail and a water collecting device thereof. The air water-collecting sail comprises a fabric matrix and water-collecting bulges, wherein the fabric matrix is a hydrophobic fiber textile fabric, the water-collecting bulges are made from hydrophilic materials and are attached to the surface of the fabric matrix in a scattered point manner or a dot matrix manner. The water collecting device further comprises a bracket and a water-collecting slot, wherein the air water-collecting sail is obliquely arranged on the bracket in an unfolding manner, and the water-collecting slot is formed in the lower edge of the air water-collecting sail. According to the air water-collecting sail, water in air is sucked through the water-collecting bulges and converges into the water-collecting slot to be collected via the hydrophobic fabric matrix after being locally saturated; the air water-collecting sail can be used for collecting fresh water in less-rainfall and more-fog regions so as to relieve the difficulty of water resource shortage and can be used for collecting fresh water in air on an island or in a sailing process; and the air water-collecting sail is simple in structure, light, convenient and wide in use range and has larger market prospects.