This research paper aim to investigate the influence of corporate mechanisms and firm size to earning management. Corporate governance mechanisms that used in this research, such as: institutional ownership, managerial ownership, board of commissioner, audit committee, and composition of independent commissioner. The sample in this research are manufacturing companies which listed in Indonesia Stock Exchange in the year 2012-2014. Total sample in this research are 30 companies that selected with purposive sampling method. This research uses multiple regression analysis method to investigate the influence of corporate governance mechanism and firm size to earning management. The results of this research indicate that institutional ownership, managerial ownership, and composition of independent commisioner had negative significant influence to earning management. Audit committee, board of commissioner, and firm size had not significant influence to earning management. 
Keywoard: earning management, corporate governance mechanisms, firm size