This research aims to analyze the effect of family firm on tax avoidance with independent commissioner as a moderating variable. This research is a quantitative model with multiple regression method, using annual report data on manufacture companies listed in Indonesia Stock Exchange from 2013 to 2015 as a sample, thus resulting 363 of sample observations in total. Model of tax avoidance measures in this research is using Cash Effective Tax Rate as the approach. This research shows that family firms have significant and positive correlation with tax avoidance. This research also finds that independent commissioners have weaken the effect of family firm on tax avoidance.