SUMMARY
This research aims to prove the effect of managerial ownership, debt policy, and firm size on tax aggressivenesscompanies listed in Indonesia Stock Exchange in the period2008-2010. The selection ofmanufacturingcompanyas ansubject of studyoptionsin linewiththe conclusionofthe Zimmerman research (1983). Resultsfromthis study is higher the ratio of managerial ownership level sindicates lower level of the taxaggressivenessbut because the probability values above 0.05 so the first hypothesis is not proven. Meansthere is still adesire forprofitorrent seeking. Then, higher the proportion of debt indicatesdecrease in aggressive tax policy but becausethe probability values above 0.05 so the second hypothesis is not proven. It means that the addition of theproportion of debt is not always negative connotations to reduce the company's profit before tax. Yet theparticipation of creditors to monitor the performance of the debtor company participates in helping reduce thelevel of tax aggressiveness. Next, bigger the company indicates less aggressive in taxation policy and therelationship is proven because the probability value below 0.05. This condition occurs as a part of company'spolitical cost policy that tends to avoid tax audit.Keywords: managerial ownership, debt policy,firm size, and tax aggressiveness