A sham marriage or fake marriage is a marriage of convenience entered into without intending to create a real marital relationship. This is usually for the purpose of gaining an advantage from the marriage.

A marriage of convenience is a marriage contracted for reasons other than that of love and commitment. Instead, such a marriage is entered into for personal gain, or some other sort of strategic purpose, such as a political marriage. Cases where those married do not intend to live together as a couple, and typically married only for one of them to gain the right to reside in a country, are considered to be sham marriages. In many cultures, it is usual for parents to decide their adult children's marriages; this is called an arranged marriage.