The robbery took place at 2.30pm, at Sutter Road, Selection Park.
SAPS spokesman Capt Johannes Ramphora says the woman heard a noise similar to that of the motor of a car.
She noticed an unknown man in the house at a window.
Read: Robbers lock boy (8) and domestic worker in bedroom
“The man instructed her to lie down on the floor,” says Ramphora.
According to the domestic worker the man was in a hurry as he was running.
She managed to press the panic button to set off the alarm.
Ramphora says the suspect was allegedly talking to somebody else but the domestic worker says she cannot remember what he was saying.
“We couldn’t interview her as she was still in shock,” he says.
Read: Domestic worker’s scream warns man of break-in
Suspect took two TV sets, two cellphones and four remote controls valued at R26 800.
Police are investigating a house robbery case.