German Grand Coalition Government’s two years in office can be divided into two distinct phases：cooperation in the overall harmony and conflict in the dual crises. In the first phase，all parties reached a consensus，worked together and cooperated with each other in the overall harmony，as a result，a number of reform schemes were legislated，and that’s why the SPD played an important role in the first year. However，different laws were distinctively different from one another in terms of the implementation effect. The crises also spawned reforms. The refugee crisis not only broke the above situation，but also had a spillover effect，like spreading of xenophobia and populism. Conflicts and fights around the refugee policy between Seehofer and Merkel made the sister party relationship between the CDU and the CSU fall to the bottom of the last four decades，which also left Merkel beleaguered in a dual crises of internal and external troubles. Once at the top，Gabriel’s authority and charisma had also been watered down.