| This study aims to gain understanding and provide empirical evidence regarding the impact of audit committee effectiveness that is measured by size of audit committee, independence of audit committee, frequency of audit committee meeting, and financial knowledge of audit committee towards accounting conservatism. This study is conducted on non-financial companies listed on Indonesia Stock Exchange LQ 45 Index on December 2012. This study uses a model of multiple linear regression analysis to test the four independent variables. Before performing the test analysis, the data is first tested with descriptive statistic and classical assumptions test. Accounting conservatism level is measured using Givoly and Hayn model. From the result of this research, it can be concluded that financial knowledge of audit committee has an impact on accounting conservatism. It means when the number of audit committee member with financial knowledge increases, the financial report with higher conservatism level will be produced. On the other hand, size of audit committee, independence of audit committee, and frequency of audit committee meeting does not have an impact on accounting conservatism. |