Since there is no cure for the COVID-19 pandemic yet, personal hygiene management is important for protecting oneself from the deadly virus. Personal hygiene management comes from personal hygiene habits. Thus, this study investigated the association between personal hygiene habits, consumers’ infection-prevention behaviors, and the effects of social support on the latter. Data were collected using a self-administered questionnaire survey of 620 Korean adults. An online survey agency was used to conduct the questionnaire over eight days, from 18 May to 25 May 2020. Data were analyzed using structural equation modeling. The results were as follows. First, personal hygiene habits positively affected self-efficacy for infection prevention (β = 0.123, p < 0.01). Moreover, personal hygiene habits indirectly affected virus spread-prevention behaviors (β = 0.457, p < 0.000) and product-purchasing behaviors for infection prevention (β = 0.146, p < 0.01) through self-efficacy for infection prevention. Second, informational support for infection prevention increased self-efficacy influence for infection prevention on the virus spread prevention behaviors among the public (composite reliability: −2.627). Thus, continued education of the public is imperative to ensuring compliance with personal hygiene practices. Furthermore, timely dissemination of relevant information on infection-prevention practices through various media during an infection outbreak is critical.