Special Tourist Visa (STV) is provided for tourists from low COVID-19 risk countries which are determined and regularly reviewed by the Ministry of Public Health of Thailand. Note that the list are regularly updated based on the assessment of COVID-19 situation in respective countries on the dates of 15 and 30 of each month.
As of 1 November 2020, Japan is not under Thailand’s list of low COVID-19 risk countries. Therefore, tourists from Japan cannot enter Thailand. Kindly monitor the Embassy’s announcement for future update.
For more details of required documents, please follow this link: http://site.thaiembassy.jp/en/visa/type/