New Delhi railway station (station code: NDLS) is the primary railway hub for the Indian capital, New Delhi, and an integral part of Indian Railways. Situated in Central Delhi, approximately 2 kilometers north of Connaught Place, the station features 16 platforms with entrances at Paharganj (platform 1) and Ajmeri Gate (platform 16). It is also served by the New Delhi metro station.

Along with Old Delhi railway station, Hazrat Nizamuddin Railway Station, Anand Vihar Terminal, and Sarai Rohilla Railway Station, it is one of the five primary railway stations catering to Delhi state, while the additional stations, such as the Bijwasan railway station, are also being developed. Categorised as NSG-1 (Non-Suburban Grade-1) station, the station being among the busiest railway stations in India accommodates over 250 trains on 16 platforms with daily footfall of approximately 500,000 passengers which peaks to 700,000 during peak festival seasons. The station holds the record for the largest route relay interlocking system in the world.

Before the proclamation of the new imperial capital at New Delhi in 1911, the Delhi Junction railway station served the entire city; the Agra–Delhi railway line cut through what is today referred to as Lutyens' Delhi. The line ran through plans for a new capital, including space set aside for the All India War Memorial and Kingsway. The railway line was realigned along the Yamuna River and opened in 1924, coinciding with the construction of the Minto Rail Bridge.

In 1926, the East Indian Railway Company approved the construction of a single-story building and a single platform between Ajmeri Gate and Paharganj; this would eventually morph into the New Delhi railway station. The government's plans to construct the new station inside the Central Park of Connaught Place was rejected. The Viceroy entered the city through the new railway station during the inauguration of New Delhi in 1931. New structures were added to the railway station later and the original building served as the parcel office for many years.

By 1955, construction of a new station building commenced at a cost of ₹20 lakh (equivalent to ₹22 crore or US$2.6 million in 2023), and the singular platform station was officially inaugurated on 16 April 1956. Heretofore, the Old Delhi railway station served as the primary railway station for the city. The concrete exterior of the building was clad with sandstone for the 1982 Asian Games, then covered with aluminum for the 2010 Commonwealth Games.

In September 2009, the new 3-story 9,000 m² building of the station facing Ajmeri Gate was opened to the public. Later the number of platforms was increased from 12 to 16. Since 1999, route relay interlocking system implemented here, has been recognised by the Guinness World Records as the largest in the world.

New Delhi railway station has witnessed numerous initiatives over the decades to decongest it.

The 45 month-long ₹2,469 crore redevelopment project with January 2029 target completion will have new modern eco-friendly energy-saving green solar buildings on both the Paharganj and Ajmeri Gate sides, redevelopment of all 16 platforms, 7 flyovers around the station and 2 tunnels to ease vehicular traffic congestion caused by the cargo, improved integrated AI-based CCTV and security control systems, improved Passenger Amenities (spacious waiting areas, improved signage, and better accessibility with escalators and elevators) and Multimodal Transport Hub (to integrate rail, metro, bus, and other modes of transport, creating a seamless connection for passengers). Upgrade will be undertaken in 4 phases, phase-1 from Paharganj side platform 1 to 6, phase-2 platform 7 to 9, phase-3 platform 10 to 13, phase-4 platform 14 to 16. Initially, phase-1 and 2 will be undertaken simultaneously while existing platforms for phase-3 and 4 will remain in use. Once the phase 1 and 2 are complete, phase-3 and 4 platforms will be closed for the redevelopment.