Judge ML Tahaliyani’s sentence came three days after Mohammed Ajmal Kasab, 22, was found guilty of murder and waging war against India for his role in the attacks in the nation’s financial capital in 2008 in which 166 people were killed.
A death sentence must be reviewed by the High Court. Pakistani Kasab can also appeal against the decision and apply for clemency to the state and central governments.
India blames the Pakistan-based militant group Lashkar-e-Taiba for masterminding the attack.
Death sentences are carried out by hanging in India.
The special prosecutor in the trial, Ujjwal Nikam, said he expected it would take at least a year for Kasab to be executed.