Belper Town FC thought everyone would realise they were joking when they advertised their next match as being against the Spanish giants.
But they received more than a dozen calls from people wanting tickets.
Even the club's caterer was taken in and started panicking about what to cook the fictitious opponents.
"I did have a bit of a panic myself because I thought 'blimey what can I feed these lads?" said Diane Collins.
"They are all into carbs, protein and veg, not like pie and chips that our footballers get."
After being told it was a joke, she said: "I was disappointed I wasn't going to see Ronaldo but never mind."
Belper Town FC play in the North Premier League Division One South - the eighth tier of the English football pyramid.
One of the club's directors, Mike Matthews, said: "Our view as directors is that Real Madrid would merely be the warm-up game for the true match tomorrow against Kidsgrove Athletic.
"We are expecting a big crowd."
The match was advertised last Tuesday and by the morning of 1 April the club had received 15 phone calls asking for tickets.
Three people also asked Mr Matthews for tickets directly - and two of those were serious.
"They were completely unaware of the date and the sheer unlikelihood of the world's most prestigious club visiting Christchurch Meadow," he said.
A non-league football club has been left red faced after an April Fools' Day joke about playing Real Madrid went wrong.