An electroenzymatic process is an interesting approach that combines enzyme catalysis and electrode reactions. Degradation of orange II by an electroenzymatic method using horseradish peroxidase (HRP) bound on inexpensive and stable inorganic beads was studied in a continuous electrochemical reactor with in situ generation of hydrogen peroxide. HRP was immobilized on Celite®R-646 as a porous support with 2% aqueous glutaraldehyde (GA), while the protein and activity yield were 3.6 mg protein and 5,280 U per g Celite, respectively. Based on a parametric study, the operating conditions were chosen, and over 90% of the degradation efficiency of orange II was maintained during continuous operation for 36 hr. From the results of GC/MS analysis, degradation products were identified and a possible breakdown pathway of orange II was also proposed. This study shows the feasibility of an electroenzymatic process to degrade azo dye compounds in wastewater.