In the German Bundestag election in 2021，Merkel’s Union Party suffered a heavy blow. The Social Democratic Party，the Green Party and the Liberal Democratic Party formed the first coalition composed of three parties in German history，opening the “post Merkel” era. The results of this election reflect the changes of German political system from different levels，such as the change of the power balance of German political parties，the change of ideological boundaries of major political parties，the change of voter mobility，the change of voters’ trust in political parties，the change of parliamentarians’ age and professional background，etc.. The changes of political systems and the unprecedented three party cabinet situation will have an important impact on Germany’s domestic and foreign policies. In the field of domestic policies，economic and fiscal policies，climate and energy policies，promoting social justice and enhancing social security will become the focus of this government’s work. In the field of foreign policy，the current government will still focus on European integration and transatlantic alliance，and will formulate cross sectoral joint strategies to seek multilateral cooperation with countries that share common values. In the context of the conflict between Russia and Ukraine，the adjustment of German defense policy deserves attention.