Former Hey Dad! star Robert Hughes has been found guilty on nine counts of sexual and indecent assault of young girls dating back to the 1980s.

After a trial lasting five-and-a-half weeks, the jury on Monday found Hughes guilty of two counts of sexual assault and seven counts of indecent assault.

The victims were aged between seven and 15 years old at the time.

The jury was unable to reach a verdict on the other two indecency charges and will continue deliberating on Tuesday.

District Court Judge Peter Zahra has asked the 12-person jury to deliver at least a majority decision of 11 on those counts.

Sorry, this video has expired Actor Robert Hughes convicted of child sexual assault ( Claire Aird )

Hughes had pleaded not guilty to the 11 charges that he either sexually or indecently assaulted five girls between 1985 and 1990.

The nine charges he was found guilty on related to three of the five alleged victims.

As the verdicts were read out Hughes stood up in the dock and yelled: "I am innocent".

He will be sentenced at a later date.

The court heard Hughes sexually assaulted one woman when she was 14 or 15 years old in her own bed.

The youngest of the two victims who Hughes indecently assaulted was seven when Hughes put her hand on his genitals.

The other was nine when Hughes told her to swim between his legs at Manly Beach. His swimmers were pulled down.

During the trial the court heard of sleepovers at Hughes's home where the actor would walk naked into the room where the girls were sleeping and expose himself to them.

Hughes denied that, saying he slept naked and often used the bathroom at night but would never walk into the room where the girls were staying.

One of the alleged victims told the jury that when she was 14 or 15, the actor came into her room and sexually assaulted her.

The court also heard that Hughes had told the girl's mother he was going into the room to check on his own daughter, who was also asleep in the room.

He could not recall why the girl did not join them for a subsequent family holiday, but said the two families stopped talking because the girl's mother wanted to have sex with his wife, Robyn Gardiner.

Hughes family members gave evidence

Ms Gardiner, a talent agent, gave evidence in defence of her husband.

She was asked about the first time she heard of an allegation against her husband - that he exposed himself to a young girl at their home in the 1980s.

Robyn Gardiner leaves the court building after the verdict was handed down. ( AAP: Paul Miller )

"It's not as if I brushed it aside; I saw no evidence to suggest it was true," Ms Gardiner said.

The couple's daughter, Jessica Hughes, also gave evidence. Now 36, the mother of two flew from London to take the witness stand.

A sixth woman, whose accusations are not the subject of the charges, also gave evidence.

She told the jury she said to Jessica Hughes: "I told you not to leave me alone with him."

Jessica Hughes said although she was only seven at the time, she would have remembered such a remark and told her parents.

During Hughes's three days on the witness stand, prosecutor Gina O'Rourke put it to him that as the star of a popular television show he thought he could do as he liked.

"You are absolutely wrong," Hughes replied.

The court heard he would nap and meditate during breaks on set.

Women who worked as wardrobe assistants on the show told the jury they felt uncomfortable waking him from such naps because he would lie naked on the couch.

Hughes also denied that, saying it was a cold room and he always napped in a dressing gown.