Act Governing Relations between the People of the Taiwan Area and the Mainland Area Article 10

No people of the Mainland Area may enter into the Taiwan Area without permission of the competent authorities.Any of the people of the Mainland Area who are permitted to enter into the Taiwan Area may not engage in any activity inconsistent with the purposes of the permission.Rules governing the granting of permission referred to in the preceding two paragraphs shall be drafted by the competent authorities concerned and submitted to the Executive Yuan for approval.
中文原文 臺灣地區與大陸地區人民關係條例第10條
大陸地區人民非經主管機關許可,不得進入臺灣地區。
經許可進入臺灣地區之大陸地區人民,不得從事與許可目的不符之活動。
前二項許可辦法,由有關主管機關擬訂,報請行政院核定之。

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