ABSTRACT The globalization of the world‟s economy and markets led companies and nations to become world global players. Before the adoption of International Financial Reporting Standards (IFRS), different countries developed their own national accounting standards. However, movement of business toward global economy brought challenges in comparability, objectivity, reliability, understandability among others. In view of this, this paper attempts to assess the impact of International Financial Reporting Standard adoption on financial performance of organizations and to the extent at which financial performance of Guinness Ghana Breweries Limited before and after the adoption of IFRS. Ratios and descriptive design was adopted using the published financial statements of company listed on Ghana stock exchange for ten years periods. Microsoft Excel was also used to obtain the mean and Standard deviation. It observed that the adoption of IFRS in Ghana, under the profitability and liquidity ratios there were no significant impact on financial performance of an organization though it enhance credibility to financial statements. This paper therefore recommends that there is the need to bring organizations system under control and make them to fit for the service and the interest of stakeholders and needs to work on skills and expertise gap by training and workshops.