A man accused of beheading and cannibalising a fellow bus passenger in Canada has been declared fit to stand trial, his lawyer says.

Defence lawyer Alan Libman said Vince Weiguang Li will stand trial for second-degree murder for the July killing of 22-year-old carnival worker Tim McLean.

A judge ordered Li to undergo a psychiatric evaluation in August to determine whether the Chinese immigrant was competent to stand trial.

His lawyers and the prosecution agreed not to release details of Li's court-ordered psychiatric assessment because it could be prejudicial to his trial.

Li, who has been charged with second-degree murder in the slaying, has not entered a plea in the case.

"I agree that he is fit to stand trial, but the issue is whether he is criminally responsible for his actions," Libman said. "My position would be in court that he's not criminally responsible for his actions and he did not know what he was doing was wrong.

"It will be for a court to determine whether that's correct or not but that's the defence's position. He suffers from a disease of the mind."

He said Li is co-operating with psychiatrists and his lawyers and is not under a suicide watch.

The case is due to return to court on November 6.

Thirty-seven passengers were aboard the Greyhound bus from Edmonton to Winnipeg when the attack took place as the bus travelled a desolate stretch of the TransCanada Highway.

Witnesses said Li attacked McLean unprovoked, stabbing him dozens of times.

As horrified passengers fled the bus, Li severed McLean's head, displaying it to some of the passengers outside the bus, witnesses said.

A police officer at the scene reported seeing the attacker hack off pieces of the victim's body and eat them, according to a police report.