This thesis examines how European Union governance instruments have restructured the conditions of connectivity and investment cooperation with China since 2018. It argues that the EU has neither moved toward full decoupling nor simply continued an older engagement logic. Instead, it has developed a strategy of governed interdependence: the management of continued economic ties through regulatory conditionality, investment screening, subsidy control, standards-based connectivity, and economic-security reasoning. Drawing on constructivism, discursive institutionalism, weaponised interdependence, and EU regulatory-power scholarship, the thesis analyses six EU instruments issued between 2018 and 2023. The analysis shows that EU institutions reclassified openness itself, moving connectivity from a largely commercial and developmental vocabulary into one organised around reciprocity, resilience, trusted infrastructure, subsidy distortion, and economic security. The thesis contributes by adapting governed interdependence into an IR framework positioned between liberal engagement and strategic decoupling, showing EU-China policy as organised ambivalence rather than coherent strategic mastery.