Biomethane potential for slaughterhouse wastewater was determined at operation temperatures of 37°C and 30°C with pre incubated cattle manure as inoculum source. Methane yields reached values of 0,73 and 0,71 m3CH4/kg VSadd at 37°C and 30°C respectively. The statistical analysis showed that no significant differences in the maximum methane production exist at the different temperatures evaluated. Additionally, energetic potential of slaughterhouse wastewater was evaluated. Wastewater produced monthly in the slaughterhouse case of study would produce 16440 m3CH4, by mean anaerobic digestion. Methane production corresponding to approximately 47% electric energy (31235kwh) and 49% (62500kwh) of thermal energy of slaughterhouse consumption.