Abstract:The criminal defense is the hold of the equilateral triangle form which is consisted by the Prosecution, Defending and Trail. It is also the important means of developing the rule of law in the society. However, China' s criminal defense is now getting into the difficult and unusual position. Thereby, it is urgent to reform and perfect the criminal defending institution in our country and lead it to the correct path. To this point, the writer thinks that the foundation of perfecting the defending institution first is to change people's idea on jurisdiction, and then to perfect the related institutions.