In recent times, companies are increasingly focusing on managing quality and addressing environmental concerns. It is important for companies to fulfil stakeholder goals, including meeting the increasing expectations of customers, complying with regulations, and contributing positively to society. In response to these challenges, many organizations are turning to international standards such as ISO 9001 (Quality Management Systems) and ISO 14001 (Environmental Management Systems). These standards are utilized as tools to help companies improve their operational aspects and meet specific criteria. ISO 9001 is designed to significantly maximize the operational capabilities of businesses. It functions as a toolkit dedicated to improving efficiency, ensuring customer satisfaction, and minimizing unnecessary waste. Meanwhile, on the environmental aspect, ISO 14001 emerges as the foremost standard. By aligning with ISO 14001, businesses aspire to achieve more efficient resource utilization and a reduction in waste generation. This research focused on an examination of manufacturing companies listed on the Indonesia Stock Exchange from 2017 to 2019. The study explored the comparative outcomes between companies that have adopted ISO 9001, ISO 14001, both certification, and those that have not. The study compared financial performance (ROA & ROE), market performance (MTB and Tobins Q), and Efficiency (TFP). To investigate significant differences between ISO certified (ISO 9001 and ISO 14001) and non-certified manufacturing companies, the research employed Mean statistics, Kruskal Wallis, Median, and Mann-Whitney U Test. Based on the Kruskal-Wallis test, the data from 2017 and 2018 show significant differences among the groups for ROA, ROE, and TQ. Meanwhile, the 2019 data revealed a significant difference only for TQ. Furthermore, the results of the Mann-Whitney U test highlighted differences in companies with only ISO 14001 certification but found no evidence of differences in companies with only ISO 9001 certification, those with both certifications, and those without any certifications. It suggested that companies could benefit more from focusing on environmental management practices associated with ISO 14001 certification.