Microscratch　experiment　was　carried　out　on　copper　with　the　Rockwell　C　diamond　conical　indenter　to　investigate　the　effect　of　normal　load　on　microscratch　test　of　the　sample.　Results　show　that　as　normal　load　increases,　both　penetration　depth　and　residual　depth　increase　linearly,　and　elastic　recovery　rate　decreases　linearly;　scratch　width　increases　nonlinearly　during　the　initial　stage　and　then　rises　linearly　with　the　increasing　penetration　depth.　When　normal　load　varies　from　0.08　N　to　0.11　N,　the　friction　force　increases　linearly,　the　friction　coefficient　tends　to　keep　constant,　and　the　friction　mechanism　is　adhesion　friction;　when　normal　load　varies　from　0.11　N　to　17　N,　both　the　friction　force　and　the　friction　coefficient　nonlinearly　increase,　and　the　friction　mechanism　is　ploughing　friction;　when　normal　load　varies　from　17　N　to　28　N,　the　friction　coefficient　tends　to　keep　constant,　the　friction　force　increases　linearly,　and　the　friction　mechanism　is　micro-cutting.　©　2020,　Acta　Metrologica　Sinica　Press.　All　right　reserved.