This study aimed to investigate the association between Korean adults' electronic health literacy and active participation in health decision-making while communicating with healthcare providers. A total of 421 adults 18 years and older were recruited from a survey panel developed by a survey company and completed an online survey asking about individual characteristics and electronic health literacy. Data were analyzed using descriptive statistics, independent-samples t tests, analysis of variance, and binomial logistic regression analysis. In results, for every one-unit increase in electronic health literacy, the rate of active participation in health decision-making was likely to increase by 3.62 times compared with the rate of passive participation in health decision-making. It was also likely to increase in those with a college degree or higher, those who used both Web sites and YouTube, those who perceived online health information to be useful, those who actively participated as a patient, and those with a desire to actively participate as a patient. To encourage active participation in health-related situations or decision-making processes, educational programs or interventions to improve individuals' electronic health literacy are needed. Healthcare providers must ensure that individuals feel comfortable expressing their preferences, needs, and values.