The invention belongs to the technical field of water-borne wood paint 
authentication, and particularly relates to a method for authenticating the truth or falsity of 
polyurethane water-borne wood paint on the basis of a nonlinear 
fingerprint graph. A water-borne wood paint sample is subjected to preliminary treatment to quicken the layering of sample 
emulsion, so that an organic phase and an inorganic phase are fully separated, and an 
emulsion breaking effect on samples is guaranteed; the method is convenient for subsequent detection; if 
acrylic acid water-borne wood paint is doped in the 
polyurethane water-borne wood paint, during detection, 
acrylic acid emulsion subjected to acidolysis in 
sulfuric acid solution generates 
acrylic acid with reducing properties; and the above products aremixed in a B-Z vibration 
system consisting of H+, BrO3, Mn2+ and acrylic acid, a sample to be authenticated and a standard sample are compared according to the extraction characteristic parameters ofthe nonlinear 
fingerprint graph, and the variety as well as the truth or falsity of the sample to be authenticated can be authenticated according to an integral similarity. In addition, the method hasthe advantages of being good in reproducibility, short in 
operation time, economic and the like, and is suitable to be widely prompted and applied in 
authentication fields of the 
polyurethane water-borne wood paint.