The　temperature-dependent　mechanisms　for　hydrogen-induced　embrittlement　and　electrochemical　corrosion　in　Ni-based　superalloy　600　have　been　unravelled　by　means　of　tensile　tests　and　potentiodynamic　polarization　tests　under　electrochemical　environment.　Increasing　temperature　accelerates　electrochemical　corrosion　behaviour　and　induces　the　transition　into　intergranular　corrosion,　whereas　there　exists　critical　temperature　THE,　max,　in　which　hydrogen-induced　ductility　loss　reaches　its　peak.　Detailed　electron　microscopy　and　thermal　desorption　spectroscopy　analysis　demystify　that　intergranular　brittle　fracture　at　THE,　max　is　predominantly　driven　by　hydrogen-dislocation-grain　boundary　interactions,　compounded　by　high　diffusible　hydrogen　content.　These　findings　offer　new　insights　into　the　critical　role　of　temperature　in　modulating　hydrogen　embrittlement　and　corrosion,　contributing　to　the　design　of　materials　in　hydrogen　environment.　©　2025　The　Authors