The preparation of biogas using anaerobic fermentation of effluent obtained from Standard Chinese Rubber processing and water hyacinth planted in an oxidation pond was studied. The results showed that water hyacinth was a satisfactory raw material for the production of biogas using fermentation method. In batch fermentation, a gram of dried water hycinth produced 0.344 L biogas, of which the methane content was 62.6;. At ambient temperature (27 oC ~ 34 oC), by mixing the pre-fermented water hyacinth with effluent in a ratio of 1:3 (calculated in COD), a gram of COD of the mixture produced 0.556 L biogas (of which the methane content was 62.8;) through continuous fermentation. The volume output of biogas was 1.78 L/(L. d). This study provides an effective method for treating water hyacinth planted in oxidation pond.