In order to discuss the differences of maximum erosion rates (estimated when sample is in steady state) of bedrock in different exposure time scales by in situ cosmogenic nuclides dating method, we gathered different cosmogenic nuclides exposure ages from around the world. We selected surface rock samples with minimum exposure ages (estimated when erosion rate is zero) of 500 ka, 100 ka and 10 ka time scales from the Palaeo Daocheng Ice Cap of the southeast Tibetan Plateau to estimate the erosion rates and analyze the previous research. The results demonstrate that the erosion rate of surface bedrock is about 1 mm/ka in 500 ka time scale in the study area, while the erosion rate in 100 ka and 10 ka time scale are about 5 mm/ka and 40 mm/ka respectively. This is consistent with the results of previous studies. The literature statistics show that there is a difference of surface rock erosion rates up to a factor of 100 between 1000 ka and 10 ka time scales. Therefore, the erosion rates estimated by in situ cosmogenic nuclides represent the maximum erosion rate in certain exposure time (assumption steady state). There are larger differences of erosion rates estimated by different exposure times. It should be paid attention to the difference in exposure time scales of samples when discussing erosion rates in different areas and time scales.