Mukesh Singh, Vinay Sharma, Akshay Thakur and Pawan Gupta were found guilty on all counts earlier this week.
Judge Yogesh Khanna said the case fell in the “rarest of rare category”, rejecting pleas for lighter sentence.
The woman, 23, was attacked on a bus in December and died two weeks later.
On Friday, Judge Khanna said the attack “shocked the collective conscience” of India, and that “courts cannot turn a blind eye” to such crimes.
“This case definitely falls in the rarest of rare categories and warrants the exemplary punishment of death,” he added.
One of the convicted men, Vinay Sharma, broke down in tears as the sentence was announced.
Earlier, protesters outside the court had demanded that the four men must be hanged.
