A test method for analyzing chlorobenzene and chlorotoluenes (commonly known as COC,s) in textiles and textile products has been developed and the same has been validated as per international validation protocol. In this test method, 28 restricted COC,s in textiles were standardized by using GC MS. As a part of method validation, Detector linearity, Accuracy, Repeatability, Spike recovery, LOD, LOQ, etc. has been established. A sample preparation method using a solvent extraction method is also developed based on extraction efficiency of a few solvents. From the extraction efficiency of various solvents, Dichloromethane is found to be the most ideal solvent for sample analysis. GC MS detector linearity when measured as coefficient of determination (R2) of all the 28 coc,s in scan mode as well as sim mode is found to be more than 0.98 which is well accepted as per the guidelines of method validation. The developed GC MS parameters are found to be suitable to identify and quantify all the coc,s. All the coc,s can be identified unambiguously as all the isomers eluted with a well resolved peaks in GC . Accuracy of the test method when conducted by spike recovery study is also within the acceptable range of more than 90% with a relative standard deviation of less than 10%. Limit of Quantification of all the 28 coc,s within a calibration range of 0.01 mg/kg to 0.1 mg/kg is below 0.05mg/kg which is much below the limit values (1mg/kg) laid by international regulatory authorities. The percent relative standard deviation of repeatability as intra- assay precision and intermediate precision is below 10% which indicates that the developed test method is suitable for the intended purpose. Reproducibility when conducted as ILC study ,the Z score value of all the ten participant laboratories were within the acceptable range of below ± 2.0. Basically, ILC study involves different laboratories, different equipment, different analysts, different environmental conditions but the same test method. With all these variable parameters, the Z score value of all the laboratories is below ± 2.0 which clearly indicates that the developed test method is valid to use the intended purpose. Based on the above findings, evidence that the developed test method can be used to identify and quantify coc,s in textiles and textile materials.