I want to consult a lawyer. Now the woman is suing for divorce, and then both men and women live in the man's parents' house during the marriage.

No, since the house is the property of the man's parents and the man's parents are the owners of the property, of course, they have the right to dispose of the property, and changing the lock is a proper disposal behavior. Moreover, it is an infringement and illegal act for the woman's family to break into the house without the permission of the owner of the house. If the circumstances are serious, criminal responsibility may be borne. You can even state to the court the fact that the woman's family broke into the house privately and provide corresponding evidence, which will only be more unfavorable to the woman!