The very Rev Jonathan Greener made the short journey from the cathedral to Ladbrokes to place the bet earlier this week
And if his horse comes in he will win £1,000 to help fund improvement works at the cathedral.
First-time gambler Mr Greener, who said he had never been inside a bookmakers office before, placed the £50 each way charity bet on Wednesday.
He said: “Obviously we’re very grateful of the support from Ladbrokes.
“We’ve been neighbours for a while and it’s always nice when your neighbours get along.”
The cathedral reopened in 2013 following a year-long £3m project to restore and transform the nave of the building.
The project, which came about following a fundraising effort, saw the old pews taken out to create a more flexible open space for worship, public gatherings, concert and other community activities.
Mr Greener added: “We’ve done out the nave of the cathedral and now we’re just working on the rest of it.
“The Heritage Lottery Fund have been great but we’ve still got £150,000 to find.
“Hopefully Godsmejudge will come through.”
Ladbrokes store manager Phil Murray said: “He’s the first reverend I’ve ever seen in the shop.
“I’m not sure if any of them place bets at home or online but you don’t normally see them coming in off the street.”
Around 150,000 racegoers and 500 million people worldwide are expected to watch the world’s most famous steeplechase.
The big race at Aintree starts at 4.15pm, with 40 horses taking part.
Nineteen-time champion jockey AP McCoy will compete for the final time in what will be a record-breaking 20th Grand National appearance.
The soon-to-retire jockey, who won the race in 2010 on Dont Push It, will be riding bookies’ favourite Shutthefrontdoor.
Mr Greener’s choice, Godsmejudge, previously won the Scottish Grand National in 2013, before coming second in the same race last year.
Jockey Wayne Hutchinson will ride the horse in Saturday’s race.