Hassiba Hadj Sahraoui, Amnesty's Deputy Director for the Middle East and North Africa Programme said: "This is another bloody stain on Iran's human rights record."
"Tragically, this case is far from uncommon. Once again Iran has insisted on applying the death penalty despite serious concerns over the fairness of the trial."
Amnesty said that although Jabbari admitted to stabbing Abdolali Sarbandi once in the back, she alleged that there was someone else in the house who actually killed him.
Jalal Sarbandi, the victim's eldest son, said Jabbari had refused to identify the man.
He told Iranian media in April: "Only when her true intentions are exposed and she tells the truth about her accomplice and what really went down will we be prepared to grant mercy,"
The United Nations says Iran has executed about 250 people this year.