The purpose of our article is to examine whether corporate governance dimensions and audit reporting lags affect firm performance in Turkey. In this article 30 firms operating in BIST 30 were used. Data cover the 2013-2019 periods. To analyze relationships between variables, we used the Westerlund Cointegration test and CCE Group Estimator. According to results, there is a long-term cointegrated relationship between dependent and independent variables in both models. In both models, there is significantly negative relationship between reporting lags and ROA/ROE. There is significantly positive relationship between firm performance and board independence. This study is one of the few studies measuring audit reporting lag and different corporate governance dimensions and their impact on firm financial performance in Turkey.