Collaborative innovation is a remarkable feature of innovation ecosystem, and it is also an inevitable requirement for high-quality regional development. Using the composite system model of collaborative innovation, the evolution trend of the collaborative innovation level of the Beijing-Tianjin-Hebei regional innovation system and internal subsystems were evaluated and analyzed. The research results show that: from 2012 to 2020, the level of collaborative innovation in the Beijing-Tianjin-Hebei region had been continuously improved; the balanced evolution trend of Beijing-Tianjin, Tianjin-Hebei, and Beijing-Hebei innovation subsystems supported improving the overall level of collaborative innovation in the Beijing-Tianjin-Hebei region; the rapid growth of the order degree of the Hebei innovation system significantly contributed to the improvement of the synergy degree of the Beijing-Tianjin-Hebei region. The research results can provide some support for the implementation results of the Beijing-Tianjin-Hebei coordinated development strategy. Such suggestion as how to improve the regional innovation ecosystem and accelerate the construction of world-class city clusters during the 14th Five-Year Plan period is put forward.