3 , Ing. Abstract This study was conducted to estimate the Green House Gases (GHG) in three farming systems associated with kikuyo grass, Pennisetum clandestinum: S 1 degraded pasture (PD), S 2 pasture recovery (PR) and S 3 silvopastoral system, Pennisetum clandestinum + Acacia decurrens (SSP), where gas emission (mg/m 2 ) was evaluated by using closed atmosphere chambers during a period of nine months. A field design was used with randomized complete block with factorial arrangement was used to analyze the data. The systems SSP and PR became sinks and regulatory methane emissions during the period evaluated, with greater contributions in the SSP, finding values greater than 200 mg/CH 4 /m 2 at 60 days. As a results, CH 4 gas emission was significantly higher in PD (1.886,89 mg/m 2 ) and lower in SSP (148,28 mg/m 2 ), whereas PD has an intermediate value effect of (1.180,11 mg/m 2) . The evaluation interaction systems x day showed negative flows for the SSP and PR from 52 to 245 days. The PD was the significantly larger emitter of nitrous oxide per unit (735,6 mg/N 2 0/m 2 ) compared to PR (647,93 mg/m 2 ) and SSP (389,89 mg/m 2 ) systems. The SSP showed the lower CO 2 emission to the atmosphere. In conclusion, the silvopastoral system SSP appear to have capacity to regulate methane gas emission under the evaluated environmental conditions and balance of greenhouse gases in livestock systems.