The Norway forward was incensed with Hooper after being denied the opportunity to play an advantage in the closing moments of a thrilling Premier League match at Etihad Stadium.
Haaland was one of several City players to remonstrate with the official and he continued his protests after the game by reposting a clip of the incident on X, formerly Twitter, with the comment "Wtf", which is offensive slang.
The incident that angered City happened when Haaland was fouled in the fifth minute of stoppage time, managing to regain his footing to swivel and send Jack Grealish clear.
Hooper initially appeared to acknowledge the infringement and wave play on, but then blew his whistle to pull play back for a City free-kick.
The decision brought protests from the City players and criticism from pundits.
"I think it is an absolute shocker. I really do," said Jermaine Jenas on the BBC's Match of the Day 2.
"I'm not sure what Simon Hooper is thinking. It's clearly a mistake but it is a monster of a mistake in my opinion."
His fellow former England midfielder Leon Osman said: "It's a huge mistake - there is no getting away from that with the technology we have but I have a slight bit of sympathy. He held his hands up straight away.