Wadi Halfa (Arabic: وادي حلفا‎) is a city in the state of Northern, in northern Sudan, on the shores of Lake Nubia (the Sudanese section of Lake Nasser). It is the terminus of a rail line from Khartoum and the point where goods are transferred from rail to ferries going down the Lake Nasser. The city has a population of about 15,725 (2007).

The town is located amidst numerous ancient Nubian antiquities and was the focus of much archaeological work by teams seeking to save artifacts from the flooding caused by the completion of the Aswan Dam. The modern town was founded in the nineteenth century and is chiefly known as the headquarters (1895–1898) of the British-led Egyptian and British forces seeking to defeat the forces of Muhammad Ahmad, the self-proclaimed Mahdi. The rail line up the Nile was originally begun in 1897 to support this military buildup; it extends, via Atbara, to El Obeid and beyond into southern and western Sudan. During World War II, Wadi Halfa was a communications post for Allied forces in Africa. The town's present-day industries include a Chinese-built fish processing plant. Most of the town was relocated, largely to New Halfa, after the construction of the Aswan High Dam due to flooding.