The woman, who is in her late 50s, was alone in her family home on the outskirts of Cork on Wednesday when shortly before 9pm, she heard a noise outside.
She went out to investigate and was confronted by the three men who were wearing balaclavas.
The woman ran back into the house and was pursued by the raiders who grabbed her and tied her hands and feet to a chair.
They then threatened her, demanding cash.
The woman said she hadn’t any, but the raiders then began to search the house and found a large sum of money.
Leaving the woman tied up, they stole the family 131-C black Lexus 4x4 from the house at Dromboy South, on the main Carrignavar to Burnfort road.
The woman managed to contact her family who in turn alerted the gardaí.
She wasn’t physically injured, but was said to have been traumatised by the ordeal.
The vehicle was recovered at 9am yesterday at Kileens, near Blarney, and was forensically examined by gardaí.
The scene of the robbery was also preserved overnight and gardaí also carried out a technical examination on the house yesterday in the hope of finding clues which might identify the raiders.
They were described as being between 5ft8in and 5ft10in tall, of slim build, and all spoke with Cork accents.
Supt Pat Lehane, who is leading the investigation, said that the raiders spent around 15 minutes in the woman’s house before escaping with the money.
“One of the men was armed with what appeared to be a rifle or shotgun, another with a hammer, and the third had what could possibly have been a taser,” said Supt Lehane.
He said they may have been watching the house for at least an hour, and was anxious to hear from anybody who had seen suspicious activity in the area.
“We are also anxious to hear from anybody who saw the black jeep anywhere on the roads between Dromboy South, Carrignavar, and Kileens,” he said.
Anybody with information is asked to contact Cobh Garda Station at 021 4908530.