Diurnal dynamics of methane (CH4) and carbon dioxide（CO2）emissions were measured on three wether crossbred sheep (average weight (25±5) kg). The animals were fed ground corn and hay (at a ratio of 6∶4) in amounts that fulfilled their calculated requirements of metabolizable protein and energy. During measurements, each animal was maintained in a respiration chamber and methane and carbon dioxide outputs were recorded at regular intervals over 24 hours. The sheep were adapted to the chamber prior to measurements by being placed in the chamber for 3-4 hours followed by an hour break continually over a one week period. During measurements, inside and outside chamber temperatures and inside chamber humidity were recorded every 5 minutes. Emission of methane and carbon dioxide averaged 11g/d and 147g/d, equivalent to 4.38 kg/a and 53.66 kg/a respectively. Peak methane output occurred at 22:00 (0.808 g/day), while lowest output occurred at 0:00 (0.299 g/h). In contrast to methane output, the output of carbon dioxide concentration was relatively stable, which suggested that the dynamic output patterns of methane and carbon dioxide were not similar