GH4169　Ni-based　superalloy　was　prepared　by　wire　arc　additive　manufacturing　(WAAM)　in　this　study.　Similar　to　the　microstructure　of　other　additive　manufactured　superalloys,　the　additively　manufactured　GH4169　alloy　suffered　from　a　high-volume　fraction　of　Laves　phase,　which　is　detrimental　to　the　alloy＇s　mechanical　properties.　To　solve　this　problem,　two　different　post　heat-treatment　approaches　were　selected　to　improve　the　tensile　properties　at　both　room　and　elevated　temperatures,　which　are　the　one　with　solution　treatment　temperature　at　950　degrees　C　and　the　modified　one　with　solution　treatment　at　1150　degrees　C,　respectively.　Detailed　phase　analysis　during　different　heat　treatment　processes　was　conducted　using　both　scanning　and　transmission　electron　microscopes.　Comparative　tensile　tests　were　also　conducted　at　both　room　tem-perature　and　650　degrees　C　to　analyze　the　role　of　the　different　microstructures　on　the　deformation　responses　of　the　prepared　samples.　By　increasing　the　solution　treatment　temperature　from　950　degrees　to　1150　degrees　C,　the　volume　fraction　of　Nb-rich　Laves　phase　dramatically　decreased,　and　the　previously　Laves-phase-trapped　Nb　con-tributed　to　the　formation　of　the　strengthening　gamma　＇＇　phase.　As　a　result,　the　tensile　strength　of　this　modified　treated　alloy　is　significantly　improved　at　both　room　and　elevated　temperatures.　Additionally,　due　to　lower　volume　fraction　of　the　Laves　phase,　the　elongation　of　the　modified　treated　alloy　at　room　temperature　is　improved　by　similar　to　35%.　These　findings　provided　new　insights　into　the　post-heat　treatment　approaches　of　the　WAAM　Ni-based　superalloy.(c)　2023　Published　by　Elsevier　B.V.