摘要:The Indonesian Government reviewed back the tax amnesty in 2016. Various reactions came up along with the announcement of tax amnesty, the investors did not accept- which led to the announcement of the Tax Forgiveness regulation through the market reactions and stock market performances in Indonesia Stock Exchange. This research is to analyze event study using information based on government-related announcements to show the impact of the new regulation towards stock performance and market reaction. The effect of the announcement will be seen from the changes in stock-prices or stock-returns that provide abnormal returns in the event period as well as market reaction which reflected in trading volume. This research used stock-return data and trading volume from all companies listed in IDX in 2016 and analyzed using the Paired Sample T-Test method. The result of this research shows there are differences among the average of stock-return, average abnormal-return of stock, and stock trading volume before and after the tax amnesty announcement.