As a result of marriage

Prerequisites for naturalization as a result of marriage
(§ 5 LGBl. 2008 No. 306)

The spouse of a Liechtenstein citizen is admitted to the national citizenship upon application if:

he/she can prove a regular Liechtenstein residence of ten years before filing the application, whereby the years after the marriage count double
he/she has been living in an upright marriage with a Liechtenstein citizen for at least five years
the Liechtenstein partner has not acquired Liechtenstein citizenship as a result of marriage
Waiver of the previous citizenship
Proof of sufficient knowledge of the German language
Proof of basic knowledge of the legal system and the state structure of Liechtenstein (Staatskundeprüfung)

Link Website: https://www.llv.li/en/individuals/migration-and-integration/wedding/as-a-result-of-eheschliessung