Abstract: The method of using trifluoro acetyl acetone as chelating agent to extract Cu2+,Hg2+,Pb2+,Zn2+,Cd2+,Cr3+ from silica gel and soil sample by supercritical CO₂ was investigated.The extracts were analyzed with the atomic absorption spectrophotometry method. The experimental results showed that at 20 MPa,60 ℃ and with methanol as modifier, the metal ions mentioned above could be extracted efficiently. The recovery values for the simulated silica gel samples and soil sample were 91.0%—98.2% and 77.8%—93.9％, respectively. This method was proved to be simple, quick and without pollution, which could be applied to the analysis of heavy metal ions in environmental samples.