Abstract: The reliability of gas laser refers to the ability of finishing stipulated function in stipulated condition and time.He Ne laser is a main product of gas lasers in our country,and has fairly scale at the end of 70's.Science 1981,more than 20 units had been organized to take part in reliability test research of gas lasers in the charge of Nanjing Institute of Technology.After several years,the lost efficiency physical model,accelerated factors and the way of accelerated life test were found.This paper introduces the Fudan University's work.