The ROC Office of the President Organization Act Article 9

The Office of the President shall have one secretary-general to the president. The secretary-general shall be a special-grade political appointee and shall, under the direction of the president, take overall charge of the affairs of the Office of the President and direct and supervise all staff.The Office of the President shall have two deputy secretaries-general to assist the secretary-general with administrative matters. One shall be a special-grade political appointee and the other a political appointee who is equivalent to a 14th-grade senior-level civil servant.
中文原文 中華民國總統府組織法第9條
總統府置秘書長一人,特任,承總統之命,綜理總統府事務,並指揮、監督所屬職員。
總統府置副秘書長二人,其中一人特任,另一人職務比照簡任第十四職等,襄助秘書長處理事務。

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