This paper reviews the existing EU multilateral cooperation diplomacy and analyzes the strategies of the EU and major European countries participating in the recently emphasized Indo-Pacific strategy. The EU and the US are trying to form a multilateral structure by cooperatively responding to the real threats of both sides, Russia and China. Based on this, this paper attempts to understand the prospect of restoring the EU-US Atlantic Alliance from a complex perspective through strengthening the alliance through NATO and the EU-US countermeasures against Russia and China. Through NATO, the traditional security system in Europe, it reaffirmed existing security threats such as Russia, and adjusted the priority of threats according to the new era and situation. In addition, the EU is pursuing an interaction between EU-US cooperation in cross-issue areas such as technology covering the security sector through the Trans-Atlantic Alliance. It is believed that strengthening the confirmation of the Trans-Atlantic alliance will narrow China's options and broaden the EU's diplomatic activities and role in strong rivalry between the US and China.