This study elaborates on the measures to improve preparedness for natural disasters by elucidating the present situation of preparedness for natural disasters at home in Japan as well as the effective factors to promote such preparedness. An Internet monitoring survey was conducted throughout Japan, and valid responses (n=1,599) were obtained. To measure preparedness for natural disasters at home, we used 31 items, including the ones in the “public opinion poll on disaster management” conducted by the Cabinet Office, Government of Japan. The Internet monitoring survey revealed that approximately 30% of the respondents arranged for articles they may require in the event of a disaster and had contemplated their evacuation actions immediately after a disaster. The Internet monitoring survey results were compared with the results of the Cabinet Office, Government of Japan’s public opinion poll. It revealed that the internet monitoring survey results better represent the tendency of the Japanese people as a whole. A multiple regression analysis was conducted to determine six independent variables—age, marital status, prior disaster experience, awareness of hazard maps, disaster imminence, and communal exchanges—statistically significant as effective factors to improve preparedness for natural disasters at home. Particularly, considering a large standardizing coefficient (β) for awareness of hazard maps, it is proposed that the most effective measure to improve preparedness for natural disasters at home to comprehend the risks posed to one’s community and own house is by using the opportunities of disaster prevention education and drill rather than simply viewing the hazard maps aimlessly.