Because it is impossible to be absolutely fair when dealing with the ownership of mortgaged houses during divorce, disputes can only be resolved on the basis of relative fairness. If only the time of obtaining the property right certificate is taken as the standard, it may be obviously unfair to one party to classify the mortgaged house as personal property before marriage or joint property of husband and wife after marriage. As we all know, the acquisition of the property right certificate is often out of sync with the actual delivery time of the house, and many houses have been unable to obtain the property right certificate for reasons other than property buyers. The legislative purpose of real estate registration is to maintain the security of transactions and protect the interests of bona fide third parties, while the division of mortgaged houses in divorce proceedings is only carried out between husband and wife, and there is no conflict of interest with bona fide third parties. If the time of obtaining the house title certificate is taken as the property nature division standard mechanically, and one party pays most of the house purchase price before marriage, the house title certificate is obtained after marriage only because of various factors other than the purchaser, then it is obviously unfair for the party who paid the house purchase price before marriage to identify the mortgaged house as the property of husband and wife. In the same way, one party paid most of the purchase price before marriage, but the house was actually delivered after marriage due to the delay of the real estate agent. If the delivery time of the house is taken as the standard for dividing the nature of the house, I am afraid it is difficult to achieve a fair result. In addition, it is not in line with the original intention of one spouse to regard the behavior of one spouse participating in repaying the loan during the marriage relationship as a loan, and it also deprives him of the right to own his own property or invest in other aspects to make profits. Therefore, for the appreciation of the mortgaged house after marriage, we should consider the contribution made by the husband and wife to repay the loan and make fair and reasonable compensation.