Abstract :
This research is purpose to examine the effect of Corporate Governance Perception Index (CGPI) announcement againts the market reaction that showed by abnormal return and trading volume activity. Population in this research are companies that participated in CGPI. Samples were determined by using purposive sampling method. Sample obtained were as much 96 companies. Hypothesis testing using MANOVA with SPSS ver. 17.0. Test result show that the first alternative hypothesis (Ha1) stated there are differences in average abnormal return companies that follow CGPI that ranked top ten with non top ten, was rejected. The second alternative hypothesis (Ha2) stated there are differences in average abnormal return companies that follow CGPI who received the predicate very reliable, trusted and quite realiable, was rejected. The third alternative hypothesis (Ha3) stated there are differences in average trading volume activity companies that follow CGPI that ranked top ten with non top ten, was rejected. The fourth alternative hypothesis (Ha4) stated there are differences in average trading volume activity companies that follow CGPI who received the predicate very reliable, trusted and quite realiable, was rejected.