Ms Ban, 22, was on her way from her CBD apartment building to an overnight cleaning job at the nearby Transcontinental Hotel on the morning of November 24, 2013.

She had been in Australia for about six weeks on a youth exchange.

Crown prosecutor David Meredith told the court Ms Ban "unfortunately" crossed paths with Mr McEwan about 4am, when he allegedly "bashed" the woman in Albert Street and dragged her up some steps into Wickham Park, Spring Hill.

On Monday morning, Mr McEwan pleaded not guilty to murder.

The court heard a witness would tell how he saw a man whose description fitted the accused's dragging the woman up the stairs.

The jury was shown a hand-drawn map of the area, just a few hundred metres from the Brisbane Supreme Court where the murder trial was sitting, as the prosecutor described how the witness circled the park to see what was happening.

Mr Meredith said the accused, now 23, tried to hide the body but jumped a chain-wire fence when the witness approached before returning to his family unit in Leichhardt Street, Spring Hill.

He said the accused "later told friends and police that he'd gone out looking to kill someone".

"Alex McEwan almost immediately, when he returns to his unit about 5am, rings a number of friends that Sunday morning and confesses that he killed a girl by bashing her," Mr Meredith said in his opening address.

"He gives a similar but more detailed version to police on the night and into the morning of Monday-Tuesday the 25th and 26th of November."

The jury heard the witness found Ms Ban's body under a bush in Wickham Park and called triple zero about 4.45am but paramedics could not save her and she died of significant facial injuries.

Mr Meredith said it was likely the case would be about "mental capacity", saying the prosecution would call witnesses to dispute any argument by the defence that Mr McEwan was of unsound mind or diminished capacity at the time of the alleged murder.

The trial continues before Justice Jean Dalton from 2.30pm on Monday.