Noting the concern of taxpayers about the powers of conducting tax assessments, this article examines the Commissioner General’s powers to assess tax in light of the protection of taxpayers’ rights in Tanzania. The main data collection method deployed was doctrinal supplemented by empirical qualitative methods. The article’s findings indicate that the exercise of the Commissioner General’s power to assess tax can result in violation of taxpayers’ rights including the right to privacy, the right to presumption of innocence, the right to property, the right to object tax assessments, and the right to appeal. This situation is mainly contributed by lack of safeguards against the exercise of the powers of the Commissioner General. The article, therefore, recommends for a transparent and collaborative tax assessment process.