The national highways in India are a network of limited access roads owned by the Ministry of Road Transport and Highways. National highways have flyover access or some controlled-access, where entrance and exit is through the side of the flyover. At each highway intersection, flyovers are provided to bypass the traffic on the city, town, or village. These highways are designed for speeds of 100 km/h. Some national highways have interchanges in between, but do not have total controlled-access throughout the highways. The highways are constructed and managed by the Central Public Works Department (CPWD), the National Highways and Infrastructure Development Corporation Limited (NHIDCL), and the public works departments (PWD) of state governments. Currently, the longest national highway in India is National Highway 44 at 4,112 km (2,555 mi). India started to increase the number of lanes of major national highways to 4 or more with the National Highway Development Project (NHDP). As of March 2022 India has approximately 35,000 km of four-lane National highways.

The National Highways Authority of India (NHAI) and the National Highways and Infrastructure Development Corporation Limited (NHIDCL) are the nodal agencies responsible for building, upgrading, and maintaining most of the National Highways network. Both operate under the Ministry of Road Transport and Highways. The National Highways Development Project (NHDP) is a major effort to expand and upgrade the network of highways. NHAI often uses a public–private partnership model for highway maintenance, and toll-collection. NHIDCL uses the Engineering, Procurement, and Construction (EPC) model to build, develop and maintain strategic roads in international borders of the country.

In India, National Highways are at-grade roads, whereas expressways are controlled-access highways where entrance and exit is controlled by the use ramps that are incorporated into the design of the expressway. National Highways follows standards set by Indian Roads Congress and Bureau of Indian Standards.

India has 161,350 km (100,260 mi) of national highways as of March 2022 compared to 101,011 km in FY 2013–14. In July 2023, Union Road Transport and Highways Minister Nitin Gadkari claimed total length of the national highways in the country increased by about 59% in the span of the last nine years.

As of 2013, National highways constituted 2.7% of India's total road network, but carried about 40% of road traffic. In 2016, the government vowed to double the highway length from 101,011 to 200,000 km.

The majority of existing highways are now four-lane roads (two lanes in each direction), though much of this is being expanded to six or more lanes. Some sections of the network are toll roads. Only a few highways are built with concrete. Bypasses have been constructed around larger towns and cities to provide uninterrupted passage for highway traffic. Some existing roads have been reclassified as national highways.

The National Highways Act, 1956 provided for public i.e. state investment in the building and maintenance of the highways.

The National Highways Authority of India was established by the National Highways Authority of India Act, 1988. Section 16(1) of the Act states that the function of NHAI is to develop, maintain, and manage the National Highways and any other highways vested in, or entrusted to, it by the Government of India.