ObjectivesTo clarify changes in the implementation of personal protective measures among ordinary Japanese citizens from the early phase of the COVID-19 outbreak to the community transmission phase.MethodsThis longitudinal, internet-based survey included 2141 people (50.8% men; 20–79 years). The baseline and follow-up surveys were conducted from February 25–27, 2020, and April 1–6, 2020, respectively. Participants were asked how often they implemented the five personal protective measures recommended by the World Health Organization (hand hygiene, social distancing, avoiding touching the eyes, nose and mouth, respiratory etiquette, and self-isolation) in the baseline and follow-up surveys.ResultsThree of the five personal protective measures' availability significantly improved during the community transmission phase compared to the early phase. Social distancing measures showed significant improvement, from 67.4% to 82.2%. However, the prevalence of avoiding touching the eyes, nose, and mouth, which had the lowest prevalence in the early phase, showed no significant improvement (approximately 60%). Multivariate logistic regression analysis revealed that men and persons of low-income households made fewer improvements than women and persons of high-income households.ConclusionsThe availability of personal protective measures by ordinary citizens is improving; however, there is potential for improvement, especially concerning avoiding touching eyes, nose, and mouth.