The goal of the study was to determine low level concentrations of 3-quinuclidinol in solifenacin succinate drug substance by using gas chromatography system. 3-quinuclidinol was used as an intermediate in the process of synthesis of solifenacin succinate. The method development was initiated with solifenacin succinate, solubility of 3-quinuclidinol, extraction and miscibility studies, chosen with 6 N sodium hydroxide solution and chloroform solvents. The method of the study was validated based on the guidelines provided by ICH. The criteria were method precision, robustness, accuracy, linearity, limit of quantification, limit of detection, and individuality in terms of specificity. In conclusion, in the present study, we developed a reliable gas chromatography method which was validated based on 3quinuclidinol in solifenacin succinate drug substance. Findings of different validation criteria used shows that the proposed method in this study is accurate, robust, precise, linear, sensitive, and specific.