A NSW couple who subjected two young men boarding in their home to constant mental and physical abuse have been found guilty of detaining them in order to gain "psychological control".

The verdict was delivered in the Downing Centre District Court today after a four-week trial in which the jury was told how two young men, aged 18 and 25, came to live with the couple between 2007 and 2010, but then effectively became their slaves.

The men were kept in the house against their will and subjected to daily abuse.

"To begin with, the young men paid for board and food and there was no problem with the way the accused treated them," the Crown prosecutor in the case, John Bowers, told the jury.

"But over time they subjected them to a regime of ongoing physical and mental abuse."

The Crown alleged the men were punched and beaten with weapons, such as wooden bats and iron bars, suffering serious injuries for which they were denied proper medical treatment.

Mr Bowers said the men were made to do domestic chores under the threat of violence, including cleaning, looking after pets and caring for the couple's children. If these chores were not completed by "deadlines" imposed, the boarders were beaten. Accompanying this, Mr Bowers said, was near constant mental abuse.

"Through violence, threats and other behaviour, the two men came to believe that they had no choice but to remain in the house," Mr Bowers said. The 25-year-old boarder was told that if he left, he and his family would be harmed.

Today, after nearly a week of deliberations, the jury found the couple guilty of detaining the men without their consent and with intent to obtain advantage, namely psychological control, and occasioning actual bodily harm.

The couple will return to court for sentencing on December 13.