This research aims to examine the effect of earnings management post conglomerate acquisition to acquirers’ shareholder value. Conglomerate acquisition’s nature to destroy value and increase firm risk would force managers to inflate earnings post acquisition to show better performance. The company was presumed to inflate earnings after acquisition. Managing earnings would affect the short and long term acquisition performance. The hypothesis testing are conducted using multiple regression model with 58 conglomerate acquisition transactions in the United States metals and mining industry during the year 2000 to 2011. The empirical study shows that companies completing conglomerate acquisitions inflate earnings in the four quarters after completion of acquisition. Earnings management significantly brings negative impact towards abnormal return to shareholders.