This research aim to analyze the influence factors toward of tax planning, with understanding of tax law, tax adsminitration, loopholes, and taxpayer moral as independent variable. Subject in this study are taxpayer in Klaten tax service office. This reaserch have 100 respondens, data teken with convenience sampling. This study uses primary data collected using questionnaires. Based on the results of data analysis shows that 1) understanding of tax law has a significant positive effect on tax planning, 2) tax administration has not an effect on tax planning 3) loopholes has a significant positive effect on tax planning, 4) taxpayer moral has a significant positive effect on tax planning.