This paper describes a simple method of the preparation of ohloropentafluoroethane,known as FC-115,whioh in a mixture with FC-22 (51.2:48.8,w/w) gives the new effective refrigerant,F-502 (or R-502).The fluorination of 1-ohloro-2-iodofluoroethane by Swarts' method produces smoothly ohloropentafluroethane at 120-130℃ under atmospheric pressare. The yield is 80.3%.1-chloro-2-iodo-tetrafluoroethane can be conveniently obtained on kilogram scale from tetrafluoroethene and iodine monochloride ina stainless steel tube with 79% yiela at 50-70℃ under 5-10 atmospheric pressure.