A rare extreme windstorm struck Portugal in 1941 when Macau was suffering from the complex Second Sino-Japanese War (WWII). Macau Chinese raised funds for Portuguese windstorm reconstruction-a little-known international diplomatic charity event relevant to Luso-Chinese relations. This article reviewed the Letters of Credit (in Chinese and Portuguese) and Chinese newspapers to provide a historical overview of the charity event across geographies, nationalities, and ethnicities and uses public choice theory to explore the motivation and underlying logic of events. Following more than two months of intensive fund-raise efforts, an active fundraising process by the Chinese elite and the public culminated in a donation of HK$ 31,075.23 (equivalent to HK$ 310,752.3 today compared to the salary level at that time) to Portugal on behalf of the Macau government to assist those affected by the storm there. Initially, it conveyed the assistance and humanitarianism of the Macau Chinese for Portugal's natural disaster. Furthermore, this episode illustrates the Chinese elite and Macau government’s willingness to seek political capital and power in response to the war crisis. This research allows us better understand international diplomatic relations patterns and rethink political and social history.