state news agency IRNA reported.
Reyhaneh Jabbari, 26, was sentenced to death for the 2007 killing of Morteza Abdolali Sarbandi, a former employee of Iran's Ministry of Intelligence and Security.
The United Nations has said she never received a fair trial.
Her execution was originally scheduled for September 30, but was postponed. Amnesty International said the delay may have been in response to the public outcry against the execution.
Jabbari was convicted of murder after "a flawed investigation and unfair trial," according to Amnesty International.
The U.N. has said Sarbandi hired Jabbari -- then a 19-year-old interior designer -- to work on his office. She stabbed him after he sexually assaulted her, the U.N. has said.
Jabbari was held in solitary confinement without access to her lawyer and family for two months, Amnesty International said in a statement. She was tortured during that time.
"Amnesty International understands that, at the outset of the investigation, Reyhaneh Jabbari admitted to stabbing the man once in the back, but claimed she had done so after he had tried to sexually abuse her," the rights group said. "She also maintained that a third person in the house had been involved in the killing. These claims, if proven, could exonerate her but are believed never to have been properly investigated, raising many questions about the circumstances of the killing."
Iranian Oscar winner Asghar Farhadi joined scores of Iranian artists and musicians calling for a halt to the execution. In an open letter, Farhadi asked the victim's family to pardon her, a possibility under Iranian law.
Rights groups have criticized Iran for a surge in executions under Hassan Rouhani, in his first year as president.
According to the United Nations, Iran has executed at least 170 people this year. Last year, it executed more people than any other country with the exception of China, the world's most populous nation.