Despite the rainy morning, more than 4550 runners and walkers turned out for the Mother's Day Classic around Lake Burley Griffin.

Bonner mother-of-two Kylie Evans said it was a fun way to spend Mother's Day, while also raising awareness of a good cause.

"I thought, being a lot more active this year, I'd like to join in the fun, and it looked like a good community vibe," she said.

"It was a good fun event, even though the weather was really yucky ... I'll definitely do it again next year."

Bina Brown, a member of the Canberra Mother's Day Classic organising committee, said the event was great, despite the adverse weather.

"The atmosphere was fabulous, people put in a really big effort," she said.

"As the biggest fundraiser for breast cancer research, everyone who participates in either the run or walk or as a volunteer or makes a donation is working towards the National Breast Cancer Foundation's goal of zero deaths by 2030."

About 100,000 people took part in more than 100 events around the country, with this year's Mother's Day Classic aiming to raise $4 million to support research into breast cancer.

The event, which was started in 1998, raises money for the National Breast Cancer Foundation and is estimated to have raised more than $30 million for cancer research since it began.

Mother's Day Classic chief executive Sharon Morris said organisers had been "inspired" by the huge numbers who turned out to support the event.

Fundraising for the classic will remain open until May 16. Donations can be made at mothersdayclassic.com.au/donate/.