The public plays an important role in controlling the spread of a virus by adopting preventive measures. This systematic literature review aimed to gain insight into public perceptions and behavioral responses to the 2009 influenza A (H1N1) pandemic, with a focus on trends over time and regional differences. We screened 5498 articles and identified 70 eligible studies from PubMed, Embase, and PsychINFO. Public misconceptions were apparent regarding modes of transmission and preventive measures. Perceptions and behaviors evolved during the pandemic. In most countries, perceived vulnerability increased, but perceived severity, anxiety, self-efficacy, and vaccination intention decreased. Improved hygienic practices and social distancing were practiced most commonly. However, vaccination acceptance remained low. Marked regional differences were noted. To prevent misconceptions, it is important that health authorities provide up-to-date information about the virus and possible preventive measures during future outbreaks. Health authorities should continuously monitor public perceptions and misconceptions. Because public perceptions and behaviors varied between countries during the pandemic, risk communication should be tailored to the specific circumstances of each country. Finally, the use of health behavior theories in studies of public perceptions and behaviors during outbreaks would greatly facilitate the development of effective public health interventions that counter the effect of an outbreak. (Disaster Med Public Health Preparedness. 2015;9:207-219)