All four of them lived in or around an unauthorised slum in the south of the city favoured by hundreds of labourers, most of them migrant workers.
Bus cleaner Akshay Kumar Singh, gym instructor Vinay Sharma, fruit-seller Pawan Gupta, and unemployed Mukesh Singh were found guilty on 13 counts that included rape, murder and destruction of evidence.
After the verdict was delivered, Pawan broke down while Mukesh said that the group has to "face the consequences", according to the Press Trust of India.
Ram Singh, the regular driver of the bus used for the attack , was found hanging in his prison cell in maximum-security Tihar Jail in March.
The 32-year-old had confessed privately to his role, according to his parents, but during the trial he had denied the long list of charges including murder, rape and kidnapping.
Here are profiles of the four men convicted, as well as the fifth under-age suspect who was sentenced to three years in a correctional facility on August 31.
The brother of Ram Singh who migrated to New Delhi from Rajasthan. He frequently worked with his brother on the bus and also tried getting a job with a construction company in Delhi.
During court proceedings in April, the unmarried labourer, who has a tattoo of two swords signifying "bravery" on his left arm, told news agency AFP he was a "very hard working man" and wanted to "lead a simple life".
Aged 29 at the time of the crime, he denied the charges against him and told the court that he "respected women".
Aged 20 at the time of the crime, he denied being on the bus. He worked as a helper at a local gym and lived in the same neighbourhood as Mukesh and Ram Singh.
He had completed his schooling, unlike the other convicts who are school dropouts, and during the trial said he wanted to appear for a recruitment test for a job with the Indian Air Force.
Sharma submitted an application to the judge to be moved out of Tihar jail after being assaulted by inmates. He suffered a fractured left hand while in custody.
The youngest of the rapists, aged 19, Gupta was a fruitseller who also worked as labourer on roads and construction sites. During wedding season, he would work with a catering company.
He was arrested at the Ram Dass Camp where he lived with his cousin and was known as a friend of Ram Singh.
A married father of a two-year-old son, Thakur also worked as a helper with Ram Singh and had earlier been employed in a local liquor factory and in a brick kiln.
Aged 28 at the time of the crime, he fled from Delhi on December 17, but was arrested at his father-in-law's home in the eastern state of Bihar. His wife, Punita Devi, told the police, that if her husband is found guilty then he should be "shot dead".
A 17-year-old at the time of the attack, who cannot be named for legal reasons, is a run-away who fled his home in impoverished Uttar Pradesh state at the age of 11.
His mother told the police that he was the eldest of her six children and that she had no contact with him during his time in the capital where he had no fixed job or address.
He cleaned Ram Singh's bus and in winter slept inside the vehicle.