The Tokyo Metropolitan Government reported 260 new cases of the coronavirus on Monday.
The daily tally was below 300 for the first time since April 5.
The number is 80 fewer than a week ago, and marks the 18th straight day of week-on-week declines.
The seven-day average of daily cases is 547, or about 86 percent of the figure for the previous week.
Tokyo's total count of coronavirus infections now stands at 160,955.
Tokyo officials say the number of patients who are in serious condition is 75, down two from Sunday.
The total number of deaths in the capital now stands at 2,055.