An enzyme electrode was developed using the enzyme sulfite oxidase (EC1.8.3.1) immobilized onto pig intestine. Hydrogen peroxide produced was monitored amperometrically. All experimental parameters such as pH, temperature, buffer constituent concentration, were thoroughly investigated and optimized when appropriate. The response to sulfite concentration was linear in the range 5.2´10-6 to 1.02´10-3 M. The proposed method was found to have a correlation coefficient of 0.952 when evaluated in comparison with the standard titration method.