A bench of justices Ranjan Gogoi, R Banumathi and M Shantanagoudar said it does not need to interfere with its 1999 verdict upholding Perarivalan's conviction.
Earlier, the CBI had sought dismissal of Perarivalan's plea claiming it was devoid of any merits.
In an affidavit filed in the apex court, CBI's Multi Disciplinary Monitoring Agency (MDMA), probing the larger conspiracy aspect behind Rajiv Gandhi's assassination, had said that the role of convict Perarivalan in the conspiracy resulting in the killing of the former prime minister and others have already been upheld by the top court.
The Supreme Court today also asked the MDMA to submit its status report in four weeks.
Former prime minister Rajiv Gandhi was assassinated on the night of May 21, 1991 at Sriperumbudur in Tamil Nadu by a woman suicide bomber, identified as Dhanu, at a poll rally.
Fourteen others, including Dhanu herself, were also killed.