The Judge, Thirunavukkarasu sentenced each of them to double life term for murder and another life sentence for stealing gold jewellery.
The double life sentences would run concurrently, followed by the other one, the judge said.
He also slapped a fine of Rs 45,000 each on them.
The prosecution case was that the two persons approached 70-year-old Rajammal, engaged in farm work and living alone at Melathur village near Anthiyur on February 16, 2013 asking for some fodder for their cattle.
Investigations led to the arrest of the two, who were charged with murder.