The purpose of this study was to determine the effect of good corporate governance mechanisms and earnings quality on firm value. The independent variables used in this study are good corporate governance mechanisms (proxied into managerial ownership, institutional ownership, independent board of commissioners, audit committee), and earnings quality. The dependent variable used in this study is firm value. The data collection method used secondary data in annual reports or financial reports that have been published by mining companies listed on the Indonesia Stock Exchange for the period 2015-2018. The sampling technique used in this study was purposive sampling, while the analysis used in this study was multiple regression. Based on the results of hypothesis testing, it showed that managerial ownership has no effect and insignificant on firm value. Institutional ownership has no effect and insignificant on company value. The independent board of commissioners has no effect and insignificant on firm value. The audit committee has no effect and insignificant towards firm value. Earnings quality has a positive and significant effect on firm value.