Dinapur Nizamat, city, northern Bihar state, northeastern India. It is situated on the Ganges (Ganga) River, about 15 miles (25 km) west of Patna.
The city is a major road and rail junction and an agricultural trade centre. Industries include printing, oilseed milling, and metalworks. There is a college affiliated with Magadh University and an army cantonment. Danapur was constituted a municipality in 1887. Pop. (2001) 131,176; (2011) 182,429.