In the preparation of glyphosate Nanlin Z, the Chloride ion (Replacement) Contents in the intermediate product, the concentrated chloromethylphosphonic solution, and in the end product through the condensation reaction of chloromethylphosphonic acid with glycine are important indexes for the control of the degrees of the intermediate concentration and the final condensation reaction.In this experiment, AgNO3 quantitative precipitation method and selective chlorine electrode method using ionmeter have been employed for analysing the samples mentioned above. Practical and reliable conditions for this analysis have been found and compared.