Amid the COVID-19 pandemic, China extended significant medical aid to international communities, aiming to combat the virus's spread and foster global solidarity. However, despite the appreciation expressed by recipient governments for China's assistance, the general public's perception of China did not significantly improve. This prompts the question: why did China's COVID-19 health diplomacy fail to resonate with foreign audiences? This article delves into the cases of Thailand and the Philippines to argue that public perceptions of countries providing aid can be heavily influenced by domestic political dynamics, particularly when incumbent governments already face legitimacy challenges prior to aid delivery. By scrutinizing the implementation of China's aid and the state-to-state relations between China and incumbent governments, political opposition forces can exploit any shortcomings or missteps, placing blame squarely on the incumbents. Given the existing distrust toward incumbent governments, the public is more inclined to accept messages propagated by opposition groups, thereby hindering any positive shift in perception toward China. This perspective complements existing research that predominantly focuses on the diplomatic strategies of donor countries, suggesting instead that the domestic politics of host countries play a pivotal role in shaping the effectiveness of foreign nations' efforts to cultivate favorable images among foreign audiences.