Abstract: The prevailing 45-minute compressed oxygen self-rescuer cannot meet the demand of coal mine escape and self-help in the market.Through the contrast of old and new,theoretical analysis,numerical calculation and simulation test method,a longer duration and better self-help function's 120 minutes selfrescuer is developed.The new self-rescuer,which has new design concept,outstanding performance,a more ergonomic half mask and fire-proof material,could play agreat role in the emergency coal mine rescue.This thesis mainly introduces the working principle,the technical characteristic of self-rescuer.