Based on the waveform data observed by the Regional Digital Seismic Network of Gansu Province, we calculated the apparent stress of the M_L ≥ 2.0 earthquakes in the southern Gansu from January 2010 to August 2017, and obtained the temporal-spatial variations of apparent stress. Results show that the distribution of apparent stress with M_L2.0~2.5 and M_L2.6~3.1 was consistent, both concentrating in the border region of Sichuan and Gansu before the Jiuzhaigou earthquake. The change trend of apparent stress over time with M_L2.0~2.5 and M_L2.6~3.1 was different within the large area:The apparent stress with M_L2.6~3.1 was more apparent and increased significantly before the Jiuzhaigou earthquake, while the apparent stress with M_L2.0~2.5 declined one or two year before. The spatial variation of apparent stress with M_L2.0~2.5 and M_L2.6~3.1 became more similar when the study area was closer to the epicenter, the apparent stress kept increasing a few years before the earthquake and suddenly declined a few months before the earthquake.