A judge said Akshay Thakur, Vinay Sharma, Pawan Gupta and Mukesh Singh should be hanged after they were convicted of the brutal attack.
In his 230-page judgement, Yogesh Khanna said the severity of the crime meant it fell into the "rarest of rare" category, telling the men: "We cannot turn a blind eye towards such a gruesome crime. There cannot be any tolerance.
"The victim was tortured to the end. There is a zero tolerance in society for such a crime."
Thakur, 28, Sharma, 20, Gupta, 19, and Singh, 26, lured their victim and her male friend onto the bus last December before raping the woman, assaulting her with an iron bar and dumping her on the roadside with her friend.
She suffered serious internal injuries and died in hospital in Singapore 13 days after the attack, which triggered violent protests across India.
The men were sentenced by a judge at Saket District Court in Delhi
New laws were introduced and existing ones amended, while fast-track courts were set up to try men accused of sexual crimes.
Police used CCTV images to track the bus and arrested two of the accused within 24 hours of the attack.
The court case relied on evidence from the victim given to a magistrate shortly before her death, as well as statements from her friend, forensic evidence, fingerprints and DNA samples. Bite marks were also matched with dental impressions of the men.
A defence lawyer in the case had asked for sentences of life imprisonment, saying Indian law calls for execution only in exceptional cases.
The counsel referred to their family background and economic status and said they had clean past records.
The woman's death led to protests and changes to India's rape laws
However, prosecutor Dayan Krishnan joined the victim's family and leading politicians in calling for the men to be given the death penalty, telling the court: "There can be nothing more diabolic than a helpless girl put through torture."
Besides rape and murder, Thakur, Sharma, Gupta and Singh were found guilty of three abduction offences and various other counts, including attempted murder, banditry, destruction of evidence, voluntarily causing hurt in committing robbery and dishonestly receiving stolen property.
Defence lawyers have said they will appeal to the High Court and, if necessary, the Supreme Court.
A fifth defendant in the case, Ram Singh, was found hanged in his cell in Delhi's Tihar prison in March.
A sixth person, who was a juvenile at the time of the attack, has already been found guilty of murder, rape and kidnapping and sentenced to three years in a correction facility.
A woman lights a candle at a vigil for the 23-year-old victim
On an average, judges in India hand down 130 death sentences a year, although in the last 17 years only three executions have taken place.
India, which voted against a draft UN resolution calling for a global moratorium on executions, currently has 477 death row prisoners.
According to the National Crimes Records Bureau, 1,121 rape cases were recorded in Delhi in the first eight months of the year - double the number in the same period in 2012.
Police say the increase is due to more cases being reported.
Amy Kevlin, Correspondent for the Financial Times in Delhi describes the reaction in court to the sentence:
