A teen victim of an alleged Mexican sex-trafficking ring cried on a Brooklyn witness stand Thursday, telling a federal jury that her captors threatened her life if she didn’t prostitute herself in Queens.

The victim, identified in court papers as Jane Doe No. 1, said she was smuggled from Mexico into Queens in 2010; her captors kept her in a locked room and taught her the trade at just 14-years-old.

“‘If you don’t do this for me, I will kill your family,’” threatened Francisco Melendez-Perez, her boyfriend from Mexico and one of the five defendants on trial, she testified.

“They knew where my family lived and I didn’t want my family to be hurt,” she continued.

Prosecutors said the alleged sex-traffickers operated from 2006 to 2017 in locations across the US.

Aside from the threats to her life, Jane Doe No. 1 said her limited English also hindered her ability to escape.

“I was scared. I couldn’t go and ask for help. I couldn’t walk outside and say ‘Hey, can you help me?” she said.

At the Queens home, the victim said another woman in the home instructed her on how to be a prostitute. The victim testified she was directed to charge $35 for 15-minute sessions.

“I didn’t like it,” the woman said as she took off her glasses and wiped away tears with a tissue. “It made me feel bad.”

The victim’s testimony ended the fourth day of trial for Melendez-Perez and co-defendants Abel Romero-Melendez, Jose Miguel Melendez-Rojas, Jose Osvaldo Melendez-Rosas and Rosalio Melendez-Rojas.

The defendants were indicted charges including sex trafficking conspiracy, sex trafficking of minors, interstate prostitution, alien smuggling and money laundering conspiracy.

If convicted on the sex-trafficking charges, each defendant faces mandatory 15-year minimum prison sentences, according to a release from the US Attorney’s Office in Brooklyn.

Five additional victims are expected to testify at their trial.