Abstract: A metal reflecting layer of an aluminum or silver alloy containing gold has a lower thermal conductivity than aluminum or silver and gold while maintaining a high reflectivity, and thus an optical recording medium, particularly a magneto-optical recording medium, having a high recording sensitivity and a C/N ratio, as well as an improved durability, can be provided. The content of Au in the Al alloy is 0.5-20 at % and that in the silver alloy is 0.5-30 at %. Preferably, at least one of the group consisting of titanium, tantalum, zirconium and yittrium is added to an alloy of Al or Ag with Au, and the content of at least one of the group consisting of titanium, tantalum, zirconium and yittrium is preferably 0.3-5.0 at % in an Al-Au alloy and 0.3-12.0 at % in an Ag-Au alloy. More preferably, the total content of Au and at least one of the group consisting of titanium, tantalum, zirconium and yittrium is 1.0-15 at %.