Objective To design a quantitative criterion and grading system for injury from adverse drug reaction (ADR) in order to serve the compensation system of injury from ADR. Methods Based on the other grading system of injury cases, the independent scores and serial grades were given to the ADR injury of different organs or different levels through two turns of consultation to 27 experts from Shanghai. Results Injury from ADR was graded from stage 1 to stage 10 according to the damage degree, with 1 stand for death and 10 for slightest injury. Conclusion The grading method of ADR based on the characteristics of injury accords with the condition of China, and can provide reference for making up the compensation system of ADR injury.