This research is done at PT Multi Niaga Indotama Medan. The company is engaged in paint distributor. The objective of this study is to know the impacts in the implementing tax planning on Article 21 - Income Tax for minimizing the entity income tax of PT Multi Niaga Indotama Medan. The methods used by the writer in this research is qualitative descriptive method. The write will analyzes the implementation of tax planning on Article 21 Income Tax in minimizing entity income tax. Based on research result, conclusion of this research is that implementing tax planning on Article 21 - Income Tax with gross up method can minimize entity income tax at PT Multi Niaga Indotama Medan in year 2017. The company currently implements net method in calculating Article 21 Income Tax. Article 21 Income Tax is borne by the company with result that tax that paid by company is same with Article 21 Income Tax of employee’s income. With net method, the Article 21 Income Tax expense paid borne by the company can’t treated as fiscal expense because Article 21 Income Tax isn’t included in employee’s income. There is increasing of Article 21 Income Tax with gross up method. Therefore, the company can get tax saving in amount of Rp 9,328,600.00 with implementing gross up method.