Self-assessment system is a tax collection system that gives credence to the taxpayer to calculate, pay, and self-reported the amount of tax owed should have been based on legislation applicable tax. This study aims to analyze and determine the effect of the authority of the authority (authority) of tax and the trust of taxpayers directly and indirectly on taxpayer compliance at the Makassar Middle Tax Office with taxpayer trust as a moderating variable. This study uses 96 effective taxpayers in 2017 at the Makassar Middle Tax Office as a unit of research analysis. By using regression analysis, the results of this study show that government authority and trust in taxpayers have a positive effect on taxpayer compliance at the Makassar Middle Tax Office and the trustworthiness of taxpayers is able to moderate the relationship between government authorities and taxpayer compliance.