The proliferation of mega-projects in the international engineering market has accelerated the widespread adoption of EPC (Engineering-Procurement-Construction) and its integrated delivery models. Given the inherent complexity of large-scale international EPC projects, numerous factors can impede objective attainment, and post-deviation corrective measures often incur substantial costs. This necessitates enhanced focus on proactive identification and mitigation of deviation-inducing factors, optimization of objective achievement environments, and improvement of Chinese contractors’ project objective governance capabilities. Through case studies and literature analysis of mega-projects, this research identifies 12 objective-influencing factors specific to international EPC projects. Through factor analysis, it was verified that the integrated management capability of the general contractor is the fundamental factor, including three dimensions: design leadership capability, procurement integration capability, and construction performance capability, and weight analysis was conducted on the indicator system. This study contributes to the theoretical enrichment of objective-influencing factor research in international EPC projects while providing practical insights to enhance contractors’ risk awareness and preventive capabilities, thereby facilitating superior project outcomes.