A special CBI court held both of them guilty of the sensational double murder in Noida, at the edge of New Delhi.
Delivering the much awaited verdict at 3.25 pm, Special CBI Judge Shyam Lal said the quantum of punishment would be pronounced Tuesday.
A lawyer said the couple were in tears when the verdict was read out and insisted that they were innocent.
The Talwars were booked under sections 302 (murder), 34 (acts done by several persons in futherance of common intention) and 201 (destruction of evidence) of the Indian Penal Code. The court also booked Rajesh Talwar under section 203 (misleading the probe).
The couple was then taken away by police to the Dasna Jail in Ghaziabad.
The Talwars will challenge the judgement in a higher court, said their lawyers. The Talwars said in a statement that they were "deeply disappointed".
"We are deeply disappointed, hurt and anguished for being convicted for a crime that has not been committed. We refuse to feel defeated and will continue to fight for justice," they said.
The judgment came nearly five-and-a-half-years after Aarushi Talwar (14) and domestic worker Hemraj Banjhare were found murdered at the flat of her parents Rajesh and Nupur Talwar in Noida May 15, 2008.
The Talwar-couple is charged with murder and destruction of evidence with common intention. Rajesh Talwar has additionally been charged under Section 203 of the Indian Penal Code for lodging a false initial FIR in the case with Noida police.
A large number of media also gathered to cover the case. The police had put in place heavy security around the court premises. Security was also been tightened outside the Talwars' house in Noida's Jalvayu Vihar.
The case was initially investigated by Uttar Pradesh Police, however, a fortnight after the murders, the case was handed over to Central Bureau of Investigation (CBI) May 31, 2008.
The charges against the couple were framed May 25, 2012, and the trial began after that.
The CBI case is based purely on circumstantial evidence because of the lack of direct evidence against the two accused.
During the trial, the agency maintained that murders were committed by the two accused as no outsider seemed to be involved. Of the four persons present at the L-32 house, two were found murdered, the agency said.
Both parents have been imprisoned during the investigation. Rajesh Talwar spent almost two months in jail in 2008, before he was released on grounds of lack of evidence. Nupur was arrested in April 2012 for ignoring orders to appear in court; she was released on bail in September that year.
CBI lawyer R.K. Saini maintained that there was no proof of any outsider's entry, the scene of crime had been heavily dressed up, Aarushi's body had been tampered and Hemraj's body was concealed on the terrace of the flat.
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