Coffee pulp represents 40 % of the total weight of the berry. Pressing this by-product for further utilization yields a sugar-rich effluentjuice which has been considered as raw material for the production of biogas.Experiments with one- and two-phase anaerobic systems wereperformed.Loading ratesfor the one-phase methanogenic reactor rangedfrom 0,5 to 3 g Volatile Solids liter-l day-l, with hydraulic retention times of 10 days. When separated acidogenic and methanogenic digesters were used,thefirst phase was operated at 0.5 days HRT and a load of 56 g Volatile Solids liter-l day-l, while the retention times for the second phase rangedfrom 10 to 5 days, with loads of 0,6 to 2.4 g Volatile Solids liter-l day-l.It was concluded,from the results of the experiments, that a two-phase anaerobic digestion system is better for treating coffee pulp juice than a one-phase unit. Hydraulic retention times of 0.5 daysfor the acidogenic phase and 8 daysfor the methanogenic seem to produce stable conditions,when daily Volatile Solids loads are of the order of 55 g liter-l and J'8 g liter-l, respectively.