International quality management standard (QMS) ISO 9001 became widely accepted as a framework for product and/or services quality improvement. There are recent research conducted in order to define relationships and effects between the applied QMS and financial and/or non-financial business parameters. The effects of the applied pharmaceutical quality system (PQS) on the business performances in Serbian pharmaceutical-chemical industry are analyzed in this paper using multivariate linear regression analysis. The empirical data were collected using a survey that was performed among experts from Serbian pharmaceutical-chemical industrial sector during 2010. An extensive questionnaire was used in the survey, grouping the questions in eight groups: Implementation of pharmaceutical quality system (AQ), Quality/strategy planning (QP), Human resource management (HR), Supply management (SM), Customer focus (CF), Process management (PM), Continuous improvement (CI), and Business results (BR). The primary goal of the research was to analyze the effects of the elements of first seven groups (AQ, QP, HR, SM, CF, PM, and CI) that present various aspects of the implementation of PQS, on the elements of business results (BR). Based on empirical data, regression relations were formed to present the effects of all considered elements of PQS implementation on the business performance parameters (BR). The positive effects of PQS implementation on the business performances such as the assessment of performance indicators, continual products and/or services quality improvement, and efficient problem solving, are confirmed in the presented research for the Serbian pharmaceutical-chemical industrial sector. The results of the presented research will create a room for the improvement of the existing models in application, and for attracting interested parties that aim to commence this business standardization process. Hence, implementation of PQS is not only the regulatory requirement or advertising movement, but very important issue for the development and improvement of business performances.