Enforcement Rules of the University Act Article 26

The membership fee charged by the Student Union in accordance with Paragraph 3, Article 33 of the Act shall be limited to that related to the handling of the study, life of students and proceedings directly related to their interests.The membership fee charged by the Student Union or by students in the name of the Student Union shall not be prerequisite for the completion of enrollment.
中文原文 大學法施行細則第26條
學生會依本法第三十三條第三項規定向其會員收取之會費,應以處理學生在校學習、生活及與其權益直接有關之事項為限。
學生會收取會費或學校依學生會請求代收會費,不得列為完成註冊程序之必要條件。

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