Electrode　erosion　is　a　harmful　phenomenon　in　applications　where　thermal　plasma　appears.　However,　little　attention　has　been　paid　to　establishing　a　systematic　evaluation　methology　for　it.　This　paper　proposed　and　verified　a　framework　for　evaluating　electrode　erosion　under　repetitive　pulsed　discharges.　Specifically,　erosion　can　be　evaluated　from　the　angles　of　operating　characteristics,　macro-morphology,　micro-morphology,　and　chemical　compositions.　Pilot　experiments　on　W-Ni-Fe　and　W-Cu　electrode　erosion　were　performed　and　results　analysed　to　verify　the　validity　of　this　framework.　It　was　found　that　the　erosion　behaviours　of　W-Cu　composites　were　different　from　those　of　W-Ni-Fe　alloys　in　many　aspects,　such　as　self-breakdown　voltage　distribution,　erosion　morphology　(microstructures),　arc　plasma　channel　compositions,　etc.　For　example,　W-Cu　electrode　surface　was　split　by　long　cracks　with　∼50　μm　depth　to　200-400　μm　polygons,　while　W-Ni-Fe　electrode　surface　was　filled　by　pits　and　protrusions　with　a　typical　diameter　of　∼20　μm.　Finally,　factors　leading　to　those　differences　were　analysed　and　causal　relationships　discussed　based　on　the　results　of　this　framework.　©　2019　IOP　Publishing　Ltd.