Hemoglobin (Hb) is a member of heme-protein that can perform catalytic non-specific chain reaction in the presence of hydrogen peroxide (H₂O₂). Catalytic ability of Hb to degrade pyrene was demonstrated using soil contaminated with 14C pyrene and 10 mg pyrene /kg soil. The composition of soil was similar to previously used soil except that it had lower organic carbon content. Bench scale laboratory tests were conducted in the presence of buffer only, H₂O₂ only, or Hb with H₂O₂ for 24 h. After 24 h reaction, 0.1 and 1.3% of 14C pyrene in contaminated soil were mineralized with H₂O₂ only or Hb plus H₂O₂. No mineralization to 14CO₂ was detected with buffer only. Approximately 12.2% of pyrene was degraded in the presence of H₂O₂ only while 44.0% of pyrene was degraded in the presence of Hb plus H₂O₂ during 24 h of catalytic reaction. When degradation intermediate products were examined, two chemicals were observed in the presence of H₂O₂ only while 25 chemicals were found in the presence of Hb plus H₂O₂. While most degradation products were simple hydrocarbons, four of the 27 chemicals had aromatic rings. However, none of these four chemicals was structurally related to pyrene. These results suggest that Hb catalytic system could be used to treat pyrene-contaminated soil as an efficient and speedy remediation technology. In addition, intermediate products generated by this system are not greatly affected by composition change in soil organic matter content.