Magistrate Ajay Kumar Sharma pronounced the quantum of punishment amid tight security arrangements in the court.
Public Prosecutor Sri Chand told reporters that the court awarded death penalty to all four under IPC 302 (punishment for murder) for planting bombs at different places.
On Wednesday, the court had convicted Mohammad Saif, Mohammad Sarwar Azmi, Mohammad Salman and Saifurrehman under various sections of the Unlawful Activities (Prevention) Act (UAPA). Another accused, Shahbaz Hussain, was acquitted with the court giving him the benefit of the doubt.
The serial blasts rocked Jaipur on the evening of May 13, 2008 within a two-kilometre radius in the walled city, popular also with tourists.
Apart from these five, two accused were killed in the Batla House encounter in Delhi in the same year and five others are still absconding.