The invention provides a rare-earth terbium complex, polyurethane foam doped with the rare-earth terbium complex and application thereof. The rare-earth terbium complex has a molecular formula of Tb(BAA)<3>.2H2O. The polyurethane foam is prepared by the following steps: synthesizing an aminobenzoic acid derivative BAA by taking o-aminobenzoic acid and isatoic anhydride as main raw materials, performing coordination with TbCl3.6H2O according to a molar ratio of 3:1, synthesizing a terbium complex Tb(BAA)<3>.2H2O, and doping the terbium complex in polyurethane foam, thereby obtaining the polyurethane foam with the advantages of excellent luminescence property and high thermal stability. The rare-earth terbium complex and the polyurethane foam doped with the rare-earth terbium complex are used for detecting H2PO4<->, CH3COO<-> and / or F<->. According to the rare-earth terbium complex and the polyurethane foam of the rare-earth terbium complex disclosed by the invention, the luminescence stability of terbium ions is improved, the luminescence lifetime is prolonged, the preparation cost is low, and the method is simple and easy to operate and has wide application prospects in the fields such as biological materials, medical treatment, agriculture, daily use chemicals and the like.