The invention provides heat-collecting evaporation orthogonally-woven fabric with a coil structure. The fabric comprises a heat-collecting evaporation layer, a floating terminal-insulating layer and awater-absorbing layer, all of which are orderly arranged. The heat-collecting evaporation layer, the floating terminal-insulating layer and the water-absorbing layer are bound together as a whole bymutually-interwoven binding yarns. Additionally, the coil structure is formed by the binding yarns on the surface of the heat-collecting evaporation layer and used for increasing the area of contact with sunlight and air. The floating terminal-insulating layer is formed by weaving of warp and weft yarns. The invention further provides a preparation method, an application method and a purpose of the heat-collecting evaporation orthogonally-woven fabric with the coil structure. The fabric can float on water. Through the binding yarns, moisture can be conducted to the heat-collecting evaporationlayer from the water-absorbing layer. The heat-collecting evaporation layer absorbs heat of sunlight so that moisture evaporation is achieved. The heat-collecting evaporation orthogonally-woven fabricwith the coil structure has a three-dimensional integrated structure, is low in weight, high in strength and simple in structure. The fabric can be used for industrialized production and shows an important application prospect in the fields of seawater desalination and sewage treatment.