In November, December 2007 and March 2008, we studied the diurnal activity budgets of the Mongolian Gazelle (
Procapra gutturosa
) using group-scan-sampling for the time before, during and after the rut around DaLai Lake, Inner Mongolia. The activities of Mongolian Gazelle were divided into 6 categories: feeding, standing, moving, lying, rutting and others. The results showed: 1) Before the rut, the major behavior of the female was feeding, the time budget of feeding occupied (44.9±3.8)% of all diurnal time, the lying time was (32.3±4.8)%; During the rut the females spent (43.5±4.0)% on feeding and (29.2±2.9)% on lying; After the rut the time budget of feeding occupied (46.2±3.10)% of all diurnal time, the lying time was (28.0±4.8)%. Activity budgets of the female on standing, rutting, others changed significantly among the three periods (P<0.05),but activity budgets on feeding, moving, and lying did not change significantly among the three periods (P>0.05). 2). Before the rut, the major behavior of the males was feeding, the time budget of feeding occupied (52.6±3.8)% of all diurnal time, the lying time was (13.4±6.4)%; During the rut the males spent significantly less time on feeding (17.5±2.8)% and more time on lying (24.2±4.1)% compared with before the rut. After the rut, the time budget of feeding occupied (29.8±4.8)% of all diurnal time, while the lying time was (44.2±4.7)%. Activity budgets of the male on feeding, standing, moving, lying, rutting, others changed significantly among the three periods (P<0.05). The time budget on feeding and lying reflects on energy balance strategies. We conclude from the results that; females do not change their strategy significantly among the three periods - they try to increase their energy intake; before the rut, the male is the same as the female, but during and after the rut, the males adopt an energy saving strategy to optimize their energy balance; males aim to save energy by spending more time lying.