This study compares environmental governance and transportation infrastructure in Yulong Snow Mountain National Park (China) and Zion National Park (USA). It investigated how spatial infrastructure planning and environmental impact assessments influence ecological outcomes in national parks. Using comparative case analysis, field observation, and policy document review, the study revealed institutional differences—particularly the legally binding NEPA framework in the U.S. versus the advisory ecological assessments in China. It identified the paradox of Green Infrastructure in fragile zones, critiqued the asymmetric risk discourse, and offered institutional recommendations to embed ecological data into enforceable spatial governance. The research contributed to sustainable national park management and infrastructure planning under ecological constraints.