The new cases mark the third day in a row that Japan has recorded a daily increase of over 1,000 infections. No additional deaths were recorded on Saturday, the Ministry of Health said.
Of the 1,540 new cases in the country, 472 were recorded in Tokyo, marking the highest single-day increase of infections in the country's capital.
The source of infection could not be traced for 65% of the patients, according to the Tokyo Metropolitan Government.
Tokyo's neighboring Chiba and Saitama prefectures also posted new highest daily increases at 73 and 74 cases respectively.
Japan has recorded a total of 37,401 confirmed cases of the coronavirus, including 1,024 deaths.