The speedy upgrowth of technology is opening new fields of protective relay nowadays,the traditional protective relay has been taken place by Intelligent Electronic Device .This article is mainly to indicate different structure and characteristics between the traditional protective relay and the IED .Furthermore the merits and defects of these two different protective philosophy are provided to the users for reference. In addition ,this thesis introduces the protective coordination with the pratical case based on theoretical analysis for traditional protective relay .With this introduction, It can provide the user with more efficient way for calibration.