Akshay Thakur, Vinay Sharma, Pawan Gupta and Mukesh Singh were sentenced to death by a trial court in 2013.
The four were hanged in the capital's high-security Tihar prison in the first executions in India since 2015.
The victim died from her injuries days after being raped by six men on a moving bus. The incident caused outrage and led to new anti-rape laws in India.
The 23-year-old physiotherapy student was dubbed Nirbhaya - the fearless one - by the press as she could not be named under Indian law.