The amination of a polymer with a primary amine results in five aminated structures in different proportions: secondary ammonium, secondary amine, cross-linked tertiary ammonium, cross-linked tertiary amine and cross-linked quaternary ammonium. A new quantitative assessment method has been designed and applied for evaluation the five respective individual aminated mole tractions. The method based on a computer program named "Min SS' written in Java script which provides the best match of a set of the five individual aminated mole tractions with the experimental determined element weight tractions of four elements C, H, N and Cl constructing the aminated polymer. This is the only method being able to quantitatively analyse the polyvinylbenzylchloride aminated with primary ethylamine in details, because this cross-linked polymer is insoluble for a convenient analysis.