This　paper　presented　180　specimens　to　investigate　mechanical　properties　of　steel　fiber　reinforced　Nanoconcrete　(SFRNC)　after　elevated　temperature　through　the　method　of　compression　test,　splitting　tension　test　and　flexure　test.　The　test　parameters　effects　of　different　elevated　temperature　and　different　content　of　steel　fiber　on　mechanical　properties　including　compressive　strength,　splitting　tensile　strength　and　flexural　strength　of　SFRNC　were　analyzed　in　this　paper.　The　integrity　of　Nano-concrete　after　elevated　temperature　could　be　improved　because　of　the　mixing　of　steel　fiber,　which　could　be　observed　from　the　failure　process　of　SFRNC.　Furthermore,　mixing　of　steel　fiber　can　change　failure　mode　of　Nano-concrete　and　improve　the　ductility　of　concrete　greatly.　It　could　be　summarized　that　the　elevated　temperature　had　negative　effects　on　compressive　strength,　splitting　tensile　strength　and　flexural　strength　of　SFRNC.　And　it　also　could　be　found　that　Nanoconcrete　mixed　with　steel　fiber　can　improve　residual　compressive　strength,　splitting　tensile　strength　and　flexural　strength　of　these　specimens　after　high　temperature.