The Tokyo metropolitan government reported 5,074 new coronavirus cases on Saturday, topping the 5,000 level for the fourth straight day.
The seven-day rolling average of COVID-19 infections came to 4,719.0 per day, up 11.5 percent from the previous week, according to the capital's government.
Nationwide, the number of new infections totaled 25,492, topping the 25,000 mark for the third day in a row.
Outside the capital, 2,705 new cases were confirmed in Kanagawa Prefecture, 2,556 in Osaka Prefecture and 1,875 in Saitama Prefecture.
Despite anti-virus measures taken under the state of emergency and quasi-emergency status in hard-hit areas, Japan is grappling with its largest wave of infections yet, with the strain on the medical system showing no signs of abating.
The number of COVID-19 cases with severe symptoms rose to 1,888 cases across the country, up 72 from Friday and hitting record highs for the ninth straight day.
In the 17 prefectures where the state of emergency and quasi-emergency status were newly imposed on Friday, the number of people increased at 21 of 34 observation spots including major train stations and commercial districts from a week earlier as of 3 p.m. Saturday.
The government's subcommittee on the coronavirus response has called for reducing traffic volumes of people in the nation's capital by half compared with those in the first half of July.
However, the turnout of people on major streets in Tokyo's Ginza and Shibuya districts on Saturday fell just modestly from levels on July 10.
At the second terminal of Tokyo's Haneda airport, the number of people passing by went up slightly from the July 10 level.