This study aims to examine the concepts of concealment and collusion that arise within the economic approach to tax law, and to evaluate the issue through examples given within the scope of donations, which may be subject to both concepts. In terms of scope, the study focuses on four topics. These are, respectively, the principle of economic approach, concealment, collusion, and forgiveness. In tax law, the principle of the economic approach, along with other methods of interpretation, is used as a method of interpretation specific to tax law in order to uncover concealment and collusion, and to understand the economic essence of a legal transaction beyond its legal form. This method of interpretation allows for the economic consequences of legal transactions to be evaluated within the scope of tax law. Taxable transactions are revealed through economic interpretation, preventing certain transactions from being concealed or evaded taxation through fraudulent means. By using donations and agreements related to donations, it becomes almost impossible to determine the taxable cause of the legal transaction, and the said legal transaction is thus exempted from taxation. In this respect, the act of donation is sometimes used to disguise legal transactions as tax-exempt, both through a specific interpretation of tax law and through collusion based on the law of obligations. The study concludes that, from a tax law perspective, in order to prevent tax evasion, it is important to evaluate each donation or related contract individually, based on the principle of economic approach, to determine whether it was made to conceal or cover up another transaction in the background, and whether it caused tax evasion or fraud.