Individuals may experience positive changes or gain growths after struggling with traumas or challenging circumstances such as the COVID-19 pandemic. This study aimed to assess potential levels of posttraumatic growth (PTG) of the general public during the COVID-19 pandemic and PTG's associations with perceptions of transformational leadership in local government and public trust. The data of a probability sample of 1011 community-dwelling adults (61.2% females; Mean age = 41.2 years, SD = 15.8) in Macao, China, were collected via a telephone poll survey. Multiple regression analyses were conducted and a bootstrapping approach was utilized to test the hypothesized moderating effects and mediating effects of trust in local government on the association between perceived transformational leadership and PTG, respectively. Results showed that about half of the respondents reported at least a medium level of PTG. Whereas perceived transformational leadership in the Macao local government was positively associated with four individual aspects of PTG (i.e., appreciation of life, new possibilities, personal strength, and relating to others) as well as the overall PTG, while controlling for the demographic variables, trust in the local government showed no moderating or mediating effects in these associations. Our findings suggest the value of governments’ transformational leadership in promoting people's PTG in the face of public crises such as COVID-19. More transformational leadership behaviors, such as attending to citizens’ personal needs and conveying an inspirational vision, in government are called for to bring about greater positive responses from individuals and ensure social vitality and resilience during this long-term public health battle.