The　step　and　ramp　heat　treatments　can　improve　the　homogenization　degree　of　the　structure　in　superalloys.　However,　the　comparison　between　them　using　the　same　temperate　range　and　total　holding　time　on　the　microstructure　and　the　microstructural　stability　is　still　vague.　The　effects　of　step　and　ramp　heat　treatment　in　the　same　solution　temperature　range　and　the　same　hold　time　on　the　microstructural　stability　in　a　third-generation　superalloy　were　studied.　The　sizes　of　gamma　＇　phases　at　dendrite　cores　and　dendrite　edges　are　different,　which　is　caused　by　the　dissolution　degree　of　the　gamma　＇　phase　during　solution　treatment.　A　low　degree　of　gamma　＇　phase　dissolution　aggravates　the　dendritic　segregation.　Dendrite　segregation　makes　refractory　elements　such　as　Co,　Mo,　W,　and　Re　aggregate　in　the　dendrite　core,　and　the　TCP　phase　is　easy　to　nucleate　and　precipitate　during　long-term　thermal　exposure,　resulting　in　decreased　structural　stability.　The　investigations　in　this　study　compare　the　differences　and　obtain　optimized　processes　and　parameters　for　the　improvement　of　superalloys.