The ROC Office of the President Organization Act Article 15

The Office of the President shall have senior advisors and national policy advisors appointed by the president to provide opinions and render advice to the president. They shall serve in an honorary capacity, and their term of office shall not exceed that of the president.With reference to the preceding paragraph, the senior advisors shall not exceed 30 in number, and the national policy advisors shall not exceed 90 in number.Regulations governing the appointment of senior advisors and national policy advisors shall be prescribed by the Office of the President.
中文原文 中華民國總統府組織法第15條
總統府置資政、國策顧問,由總統遴聘之,均為無給職,聘期不得逾越總統任期,對於國家大計,得向總統提供意見,並備諮詢。
前項資政不得逾三十人,國策顧問不得逾九十人。
資政、國策顧問之遴聘辦法,由總統府定之。

English translation for reference only; the Chinese text prevails. Not legal advice.