Disclosed is a lightweight aluminum based alloy that is high in strength and elongation properties at high temperatures of around 200° C. to 300° C. and has excellent workability in hot working. Disclosed also is a heat-resistant aluminum based alloy excellent in wear resistance and rigidity. Specifically, an aluminum based alloy contains, in terms of percent by mass, 5% to 10% of Mn; 0.5% to 5% of V; 0.5% to 5% of Cr; 0.5% to 5% of Fe; 1% to 8% of Si; 0.5% to 5% of Ni, with the balance being aluminum and inevitable impurities. The aluminum based alloy has a structure including 35 to 80 percent by volume of an intermetallic compound phase with the balance being an aluminum metal matrix.