An austenitic cast iron including basic elements of C, Si, Cr, Ni, Mn and Cu; and the balance including Fe, inevitable impurities and/or a trace-amount modifier element, which is effective in improving a characteristic of the cast iron, in a trace amount; and structured by a base comprising an Fe alloy in which an austenite phase makes a major phase in ordinary-temperature region; wherein the basic elements fall within compositional ranges that satisfy the following conditions when the entirety of the cast iron is taken as 100% by mass: C: from 2.0 to 3.0%; Si: from 4.0 to 5.4%; Cr: from 0.8 to 2.0%; Mn: from 3.9 to 5.6%; Ni: from 17 to 22%; and Cu: from 0.9 to 1.6%.