Negative attitudes towards vaccines and unwillingness to receive vaccinations would be major barriers to managing the Covid-19. The present study aimed to examine factors that affect vaccination intentions, at the time when vaccination started for the non-medical population in Japan. Main factors we considered as relating to vaccination intention were general attitude toward vaccines, vaccine uncertainty, close others’ attitude toward Covid-19 and Covid-19 vaccine, life satisfaction and stress. We conducted a web-based survey in mid-May, 2021, in which 1595 Japanese (mean age＝45.3, age range＝20-80) participated. The result showed that 63.4 % of the respondents would definitely or probably get vaccinated if given the chance the following week, whereas 20.9 % were unsure and 15.8 % would definitely or probably not get vaccinated. General attitude toward vaccines and close others’ attitude Covid-19 vaccination strongly predicted vaccination intention.