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During the operation of nuclear plants, the reaction of Zr and water produces ZrO2 and hydrogen atoms, some of which enter the zirconium alloys. Hydrogen in zirconium alloys affects not only mechanical properties, but also corrosion resistance. The degree of influence is closely related to alloy composition and corrosion conditions. The corrosion mechanism Zr-4 (Zr-1.3Sn-0.2Fe-0.1Cr, mass fraction, %) alloy in LiOH aqueous solution affecting by hydrogen is still controversial. Therefore, the effect of pre-charging hydrogen on the corrosion resistance of Zr-4 in 0.01 M LiOH aqueous solution was investigated.Two batches of Zircaloy-4 specimens were pre-hydrided using gaseous or electrolytic hydrogen charging methods to obtain the predetermined hydrogen level: less than 120 μg/g H and more than 120 μg/g H. Then all the as-received specimens and hydrogen-charged specimens were corroded in lithiated water with 0.01 M LiOH at 360 ℃ and 18.6 MPa in a static autoclave. The mechanism about the effect of hydrogen on the corrosion behavior of zirconium alloys was discussed based on weight gain, microstructure of oxide films, compressive stress and Li+ depth profile in the oxide film. Results showed that Zircaloy-4 specimens with 20~250 μg/g hydrogen exhibited better corrosion resistance compared with the as-received ones. The corrosion resistance of Zircaloy-4 became better with increasing the hydrogen content. The integrity of the oxide film on the hydrogen-charged specimens was better than that on the as-received specimens, which indicates a slower microstructural evolution of the oxide film on the hydrogen-charged specimens. The hydrogen-charged specimens had a less undulate oxide/metal interface. Compared with the as-received specimens, the compressive stress in the oxide film on the hydrogen-charged specimens was lower and showed a less gradual gradient with the increase of oxide thickness. The concentration of Li+ in the oxide film on the hydrogen-charged specimens was lower, and it dropped down quickly along the depth of oxide film. In this way, the microstructural evolution of the oxide film was retarded and the corrosion resistance of Zircaloy-4 was improved by pre-charging hydrogen.