The tax declaration is the most important source of information for the tax collection agency to calculate the taxable income of the taxpayer. In order to review the correctness of the statements in the tax return, field review became a necessary tool. However, tax information exchange can also provide assistance. The so-called tax information exchange refers to a tax collection and collection authority that informs the tax collection and collection authority or the administrative agency that the important tax collection file is held, or that the public legal person informs the tax collection and collection authority, and does not wait for the other party. Request in advance, that is, spontaneous or automatic notification. But tax information exchange can also be done by private individuals. Although the administrative agency or the private company has the obligation to transfer important information due to legal provisions, the act of transferring the information can be exercised in discretion or freely. Under the globalization and the world’s network, tax residents have become the norm across borders, and as a result, their wealth has easily escaped the tax collection agencies of the country. Under this circumstance, the tax collection agencies of various countries need strong cooperation to prevent wealth from being improperly concealed. Whether it is spontaneous provision, automatic exchange or information exchange required, here is the need for greater transparency and more tax fairness. However, a country may not exercise its investigative powers in other countries, and therefore requires international law agreements. Through these agreements, in particular, the parties have handed over important tax factual information to both parties, thus enabling each country to properly levy taxes. To this end, these agreements refer to the Double Taxation Relief Agreement, the OECD Tax Model, and the OECD’s request to respond to the G20 countries to develop a joint declaration for the automatic exchange of information on financial accounts. Guidelines.