Enforcement Rules of the Household Registration Act Article 2

The authority in charge of household registration administrations shall be the Civil Affairs Bureau of municipal and county (city) governments.
中文原文 戶籍法施行細則第2條
為辦理戶籍行政業務,在直轄市、縣(市)政府為其民政機關(單位)。

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