Kenya's world record holder and Olympic silver medallist Brigid Kosgei will defend her London Marathon title in this year's race on 3 October.
The 27-year-old is aiming for a third successive title in London after also winning the race in 2019.
Last year’s men’s marathon winner Ethiopia's Shura Kitata also returns but World record holder Eliud Kipchoge misses out.
This year's edition will involve 50,000 runners completing the traditional course from Blackheath to The Mall.
"It is a great feeling to be coming back, as London is one of my favourite marathons. Last year's win was very special, particularly given what the whole world was going through," said Kosgei.
Kosgei will be up against New York champion Joyciline Jepkosgei and Ethiopia's Roza Dereje who is the 10th-fastest woman of all time over the distance.
Also in the field is Australia's Sinead Diver, born and raised in Ireland, who finished 10th in the Tokyo Olympic marathon at the age of 44.
Ethiopian duo Mosinet Geremew and Mule Wasihun will also compete in the men’s event with Evans Chebet flying Kenya’s flag in London.
Kitata who dropped out of the hot and humid conditions in Sapporo says he wants to make amends in London in eight weeks time.
"I just did not adapt to the weather well," he said. "It was very cold in Ethiopia prior to leaving for Tokyo and when we got there, the weather took its toll on my body and made my breathing very hard.
"Winning last year was an unforgettable memory and it gave me huge excitement to bring back such a big victory to my country."