The objective of this study was to evaluate the effect of the adding increasing levels of biochar on in vitro methane and carbon dioxide production and organic matter (OM) digestibility. The experimental design was a completely randomized design with 5 treatments and 3 replications per treatment. The five treatments were addition of five levels of biochar; 0; 0.5; 1.0; 1.5 and 2.0% corresponding to BC0; BC0.5, BC1, BC1.5 and BC2, respectively, to para grass (Brachiaria mutica) mixed with 20% of concentrate (DM basis). Total gas, methane and carbon dioxide productions at 0, 6, 12, 24, 48 and 72h were determined. The results of this study showed that the total CH4 production (ml/g OM) and organic matter digestibility (%) at 72h incubation were significantly decreased (Pfor the BC0 treatment (50.8ml/g and 74.9%, respectively). It could be concluded that adding biocharto the para grass from 0.5 to 2.0% mixed with 20% of concentrate could reduce methane production from 3.3 to 20.2%, however the reduction of OM digestibility was also found. In vivo experiments in ruminants by adding the biochar to diets should be evaluated greenhouse gas production and nutrient digestibility for the applied studies.