Rachael Buckland, 25, was getting ready for bed at her home in St Mellons, Wales, when she lost her footing and fell down the stairs on Wednesday night.
She suffered a bleed on the brain and is currently in an induced coma at the University Hospital of Wales in Cardiff.
The former bantamweight Welsh champion is married to undefeated Celtic boxing champion Mitchell Buckland, 23.
A fundraising page has been set up to help the family which has so far raised more than £1,500.
The mother-of-two used to work at the Tom Toya Lewis pub in Newport and the pub will be holding an all day fundraiser on Wednesday.
Joined by boxers from St Joseph”s, staff will be on an exercise bike from 8am until closing time to raise money.
St Joseph”s gym have organised an auction of sports memorabilia to be sold to raise funds, including a gold pair of gloves signed by British champion Andrew Selby.
Tony added: “It”s great to see the boxing community come together for her.”