Abstract: Exploring the historical evolution process of the limit of justifiable defense home and abroad is of great importance for the study on the development of the system of justifiable defense.On the limit of justifiable defense,every country experienced a long and complicated process from loose restriction to narrow restriction,and then to loose again.It is justice that urges people to use the weapon of defense to safeguard their rights,it is rationality that spurs people to restrict their defense while struggling against unlawful infringement,and it is evil that compels people to loosen the limit of justifiable defense again after consideration.