Abstract: Beijing, Tianjin and cities of Hebei Province form an important urban agglomeration in Northern China. Integrating transportation networks is an efficient way to boost the development of this area. Based on the data of the most convenient traffic network of Beijing-Tianjin-Hebei in 2000 and 2015, using ArcGIS network analysis, the change of accessibility of nodes was detected. In the research method, we highlighted the most time-saving section of a traffic network system and weighted average travel time improved by degree centrality. The findings are as follows. The accessibility pattern of Beijing-Tianjin-Hebei area has changed greatly, with the overall accessibility upgraded, and the one hour transportation area expanded. The accessibility within the region decreases in the following order: central cities, eastern and southern cities, northern cities. Shift of transportation modes has greatly improved regional accessibility, with a weighted average travel time between cities generally reduced by more than 50 percent. And the rate of change in the central and southern cities in the region is much greater than that in northern cities. Accessibility of Zhangjiakou and Chengde were the lowest in the region, hindered by the mountain topography and transport infrastructure constraints.