[en] Highlights: • Grain boundary engineered microstructure achieved in alloy 617 by strain annealing. • Grain boundary engineered microstructure showed improved resistance to hot corrosion. • Cr depletion at grain boundaries observed in non grain boundary engineered sample. • S segregation occurred at random high angle boundaries. - Abstract: The role of grain boundary engineering (GBE) on high-temperature hot corrosion behavior of alloy 617 was evaluated by exposing both the as-received (AR) and GBE specimens in a salt-mixture of (75% Na_2SO_4 + 20% NaCl + 5% V_2O_5) at 1273 K for 24 h. The AR specimen having continuous network of random high angle grain boundaries (HAGBs) has undergone hot corrosion and substantial depletion/segregation of alloying elements through the entire cross section. The GBE specimen exhibited significantly reduced hot corrosion and depletion/segregation of alloying elements. This is attributed to the high fraction of 3-CSL triple junctions which break the percolation in the random HAGBs network.