The effects of pH, temperature and sucrose addition on biodegradative capacity of Fusarium sp. HJ01 for 4-chlorophenol (4-CP) were examined, the property of dioxygenases produced by Fusarium sp. HJ01 during 4-CP degradation was investigated. The results show that Fusarium sp. HJ01 has a high capacity on degrading 4-CP in solution. The optimum values of pH, sucrose concentration and temperature are pH 7,1 g/L and 30 degrees C, respectively. The strain can produce chlorocatechol 1,2-dioxygenase (CC120) and chlorocatechol 2,3-dioxygenase (CC230), which show the highest activities when 4-CP is used as the sole carbon source and energy, and the optimal values of pH and temperature are pH 7 and 50 degrees C for CC120 as well as pH 8 and 60 degrees C for CC230. The kinetics of enzyme-catalyzed reactions accord with the Michaelis-Menten equation. To our knowledge, this is the first study on biodegradation of 4-CP by Fusarium sp. HJ01. (C) 2010 Elsevier Ltd. All rights reserved.