Act for Implementation of J.Y. Interpretation No. 748 Article 5

Person of the same sex may not form a union as stated in Article 2 with any of the following relatives:(1)A lineal relative by blood or by marriage;(2)A collateral relative by blood within the fourth degree of kinship. The limit to form a union shall not be applicable to persons of collateral relative within the fourth degree of kinship by adoption.(3)A collateral relative by marriage within the fifth degree of kinship of different rank.The union prohibitions between lineal relatives by marriage provided in the preceding paragraph shall continue to apply even after the dissolution of relations between relatives by marriage.The union prohibitions with the lineal relative by blood or by marriage set forth in the first paragraph hereof shall be applicable to persons of lineal relative by adoption after ending of the adoption relationship.
中文原文 司法院釋字第七四八號解釋施行法第5條
與下列相同性別之親屬,不得成立第二條關係:
一、直系血親及直系姻親。
二、旁系血親在四親等以內者。
但因收養而成立之四親等旁系血親,輩分相同者,不在此限。
三、旁系姻親在五親等以內,輩分不相同者。
前項與直系姻親成立第二條關係之限制,於姻親關係消滅後,適用之。
第一項與直系血親及直系姻親成立第二條關係之限制,於因收養而成立之直系親屬間,在收養關係終止後,適用之。

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