The invention provides a stress corrosion and hydrogen measuring electrochemical in-situ measurement device under a slow strain speed condition. The stress corrosion and hydrogen measuring electrochemical in-situ measurement device comprises an electrochemical work station, an auxiliary electrode, a working electrode, a reference electrode, a stretching test sample, a slow strain stretching machine, a computer, an isolation transformer, a corrosion device and a hydrogen measuring device. The stress corrosion and hydrogen measuring electrochemical in-situ measurement device has the effects that an electrochemical in-situ test can be carried out on stress corrosion and hydrogen permeation respectively under the slow strain speed condition through replacing a corrosion electrolytic tank; the device has the characteristics of adjustable test sample size, in-situ electrochemical measurement, accurate load-displacement readings, simple structure, convenience and flexibility in utilization, simplicity in operation and the like. The device can be used for simultaneously realizing in-situ electrochemical behavior detection of pull stress, corrosive liquid, corrosive gas and temperatures, and can be widely applied to researches of strain speeds, the pull stress, types and concentrations of corrosive media, pH values, temperatures, corrosive gas partial pressure and concentration and influences on corrosion of metal materials by hydrogen brittleness, and a damage evolution rule of materials can be analyzed through electrochemical data.