Visual titrimetry, spectrophotometry, and streaming current detector(SCD) method for end point detection are described for the charge determination of the synthetic cationic polymers of different charge density and molecular weight. The charge densities for each of the cationic polymers by spectrophotometry and SCD method were in good agreement with each other. The results obtained by visual titrimetry are less reliable, compared to other methods, especially for polymers low charge density. With spectrophotometry and SCD method, the titration curves have a sharp break point in the range of the end point reaction for polymers of high charge density, which becomes rather less sharp for polymers of lower charge density. The charge densities for polymer A-L, which are copolymers of polyacrylamide and dimethylaminoethyl acrylate, show pH dependence, becoming lower as pH increases, but the charge density of polydiallyldimethylammonium chloride are independent of pH in the pH range investigated.