About a dozen officers with Operation Hammer are carrying out warrants at the MUHC's Guy Street offices and meeting with several people linked to the investigation.
A spokesperson for UPAC says there are fewer than five warrants being executed, but they are part of an "important operation."
She said few details about the investigation would be released at this time.
The MUHC confirmed that investigators with the anti-corruption unit arrived at its offices on Guy Street at 8 a.m. Tuesday looking for information related to the awarding of contracts for the Glen site of the new superhospital.
The project, a public-private partnership, was awarded in 2010 to the consortium Groupe immobilier santé McGill.
The MUHC said it is cooperating fully with investigators and wouldn't comment further.
Other searches are expected to be carried out on the island of Montreal today.
No arrests have been made.