A scroll compressor, in which as a coolant is applied a mixture coolant obtained by mixing at least one or more kinds selected from a group of hydro fluoro carbon, within a closed container thereof, comprising: an electricmotor; a rotary scroll driven with said electric motor; and a stationary scroll, whereby forming a scroll compression mechanism between said rotary scroll for compressing said coolant, wherein said scroll compression mechanism comprises: Oldham ring for supporting said rotary scroll so that said rotary scroll perform a gyrating movement with respect to said stationary scroll without spinning around an axis thereof; and a frame for supporting said Oldham ring in movable manner for purpose of achieving supporting of said rotary scroll mentioned above, wherein said Oldham ring is formed from sintered alloy of iron group, while said frame and said rotary scroll are formed from cast iron, and after treating a steam process thereon, a sliding surface of said Oldham ring is machined by means of an end mill.