European football's governing body have strict guidelines when it comes to player gambling and Wilshere has been hit with an official warning after hinting that he had flouted those rules.
The 20-year-old midfielder took to Twitter in December to comment on a Champions League match involving Arsenal.
Injury kept the England international out of the meeting with Olympiakos, but he wrote that fellow Gunner Emmanuel Frimpong was 'worth a cheeky £10' to open the scoring against the Greek outfit.
After seeing his colleague hit the side-netting with the scores locked at 0-0, Wilshere added: "Frimmy nearly won me some money there!"
He later insisted that he had only been joking about placing a wager on the game, tweeting: "I didn't actually bet on the game. I know we're not allowed to! I was only messing just to be clear."
UEFA have, however, conducted a seven-month investigation into the matter and have warned the Arsenal man as to his future conduct.
A UEFA spokesman said: "The player has been warned for being in breach of the principles of integrity of matches and competitions.
"The disciplinary measure was a warning."