The invention discloses normal-temperature cured water-based polyurethane and a preparation method and application thereof. The polyurethane is prepared from polyether polyol, fluoride glycol, polyisocyanate, anti-mildew bactericide dimethyl fumarate, diluent, molecular weight modifier, fluorine-containing hydroxyl acrylate monomer, methacrylic acid-2-hydroxypropyl ester, chain extender, neutralizer and coupling agent. By means of the addition polymerization mode of unsaturated double bond containing polyether polyol, polyalkoxy silicon base and fluorine-containing hydroxyl acrylate are chemically bonded into polyurethane chains, novel water-soluble polyurethane resin of a polyalkoxy silicon base fluoro modified acrylic resin-polyurethane interpenetrating polymer networks (IPN) structure is synthesized and is made to have the common advantages of water-based polyurethane paint and polyacrylate emulsion, and the polyurethane is cured at normal temperature, has oil resistance and stain resistance, is suitable for waterproof and anti-foul coating on surface layers of leather, plastic, wood, metal, external walls and the like, and is environmentally friendly, high in industrial practicability and high in economic benefit.