In mainland China today, marriages between first cousins are generally prohibited both legally and socially. However, this was not always the case historically. Here is an overview of China’s evolving stance on cousin unions.

Past Periods of Legal Acceptance

Cousin marriage has not been consistently prohibited throughout Chinese history. In fact, various dynasties allowed and even encouraged marriage between cousins, nieces/nephews, and other close relatives as a way to strengthen family ties.

However, sentiments began shifting in the early 20th century toward restricting consanguineous marriages, particularly among elites and Christians influenced by Western norms. Still, legal prohibitions were only sporadic initially.

Current Legal Prohibitions Nationwide

Today, the Marriage Law of the People’s Republic of China legally prohibits marriage between lineal relatives by blood as well as collateral relatives up to third cousins. This includes first cousins.

The ban was enacted in 1981 due to concerns about potential health risks associated with consanguineous marriages, especially among more closely related couples.

Social Norms Also Discourage Cousin Marriage

In addition to legal prohibitions, cousin marriage is also viewed unfavorably by most of Chinese society today. Many consider it incestuous and harmful to offspring.

Surveys indicate over 80% of Chinese citizens oppose marriages between first cousins. Social norms align with legal rulings in discouraging the practice nationwide.

Special Status of Hong Kong and Macau

However, the two special administrative regions of Hong Kong and Macau remain exceptions. Since they maintain independent legal systems, no prohibitions on cousin marriage exist in these territories.

But even here, cultural opposition persists, indicating more universal social taboos against the practice within Chinese society.


In summary, cousin marriage is broadly prohibited and discouraged in China outside of Hong Kong and Macau. Both legal barriers and social norms impose hurdles for cousin couples throughout most of the country.