This is the first empirical study to compare the health information-seeking behaviors among the middle-aged groups and older adults. The purpose of this research paper is to explore how middle-aged and older adults use different sources to acquire health information, their perception of information quality, and information processing behaviors. A survey study was conducted among 786 Hong Kong residents aged 40 to 69. The study found that respondents relied heavily on their families and friends to obtain health information. Although professionals were the second least used information source for health information, it was considered the most credible one among the respondents. New media was perceived as the least used as well as the least credible source for health information. Older adults more relied on traditional media and professionals to get health information while middle-aged adults more frequently used new media to obtain health information.