Legal analysis: If the parents of the man make a down payment of mortgage to buy a house before marriage, it belongs to the man's personal property if it is registered in the man's personal name, and the part jointly repaid after marriage belongs to the husband and wife's common property, and it will be divided equally in principle. If registered in the names of both parties, it belongs to the gift of the man's parents to both men and women and belongs to the joint property of husband and wife.

Legal basis: Article 1062 of the Civil Code of People's Republic of China (PRC), the following property acquired by husband and wife during the marriage relationship is the joint property of husband and wife: (1) wages, bonuses and labor remuneration; (2) Income from production, operation and investment; (3) Income from intellectual property rights; (4) Inherited or donated property, except as provided for in Item 3 of Article 1063 of this Law; (5) Other property that should be jointly owned. Husband and wife have equal rights to dispose of common property.