A rabbit and chicken terrine entree could be to blame for a suspected food poisoning outbreak which hit more than 30 guests at an official Anzac AFL luncheon.

A suspected food poisoning outbreak at an official Anzac Day AFL luncheon left more than 30 guests distressed and light headed, with some fainting.

AFL boss Gillon McLachlan and Governor Linda Dessau were among the guests at Thursday's Essendon's president's lunch MCG event, with both avoiding any illness.

"It happened very quickly and people ... were being affected at the same time," McLachlan told 3AW radio, adding that the cause of the gastro upset is due to be known later on Friday.

Food poisoning floors AFL Anzac guests.

"I didn't see vomiting. I saw people fainting and I saw people distressed and ... light headed. I think (there was) a level of pain, but light headedness I would have said."

One guest told 3AW that all the affected people are believed to have eaten a rabbit and chicken terrine at the event in the Olympic Room.

An ambulance spokeswoman confirmed some people were hospitalised.

McLachlan suggested most affected guests had bounced back from the episode.

"We don't have a longer-term issue," he said.

The venue's operator, Melbourne Cricket Club, is trying to pinpoint what sparked the illness.

"We are currently investigating to determine the cause of these incidents," a statement read.

"We are working in co-operation with health services and our partners to understand what caused the medical issues."

It is understood the terrine was served as an entree and numerous people walked out, fearing they would faint ahead of the Bombers' four-point win over Collingwood.