The high-temperature and high-pressure gas-phase thermal hydrogen charging method was used to introduce hydrogen into GH690 nickel-based superalloy with a concentration of 38.1 mg/kg. The results show that hydrogen has no obvious effect on the yield strength of GH690 alloy, but the yield step of the hydrogen-filled sample disappears, and the tensile strength and elongation at break of the alloy are significantly reduced. Fracture analysis showed that the unhydrogenated samples were mainly characterized by ductility ligament fracture, while the hydrogen-filled samples showed brittle along the crystal fracture. When GH690 alloy is tensile deformed, hydrogen easily migrates to the grain boundary with the movable dislocation in the form of Cottrell air mass, and with the plastic deformation, the dislocation accumulates at the grain boundary, resulting in hydrogen enrichment at the grain boundary. The enrichment of hydrogen at the grain boundary reduces the grain boundary bonding strength of the alloy, so that microcracks are easy to germinate at the grain boundary, resulting in fracture along the grain.