The name of the town means "trawlers" in Romanian, indicating that it was originally a fishing village.
The settlement was mentioned for the first time in 1421 under the name Kara Koyun ("Black Sheep"), to be renamed later on Karaköy or Carachioi ("The Black Village"). In 1927, the locality was again renamed to Năvodari and after five years, on 15 August 1932, it was recognized as a commune.
The town developed during the communist regime as part of the industrialization program. In 1954, the construction of the superphosphate and sulfuric acid plant, also known as USAS. (Uzina de Superfosfat si Acid Sulfuric, Superphosphate and Sulfuric Acid Factory), begins, which was put into function with its first line in 1957, opening the road towards the industrialization of the area and the growth of the population. The factory polluted the Black Sea and Taşaul Lake with toxic dumps. In the 1990s, the pollution was greatly reduced as the factory was modernized.
In 1968 the population of Năvodari exceeded 6,500 inhabitants. The Law No. 2/20.12.1968 granted the commune of Năvodari town-status and placed under its administration the Mamaia Sat village.
The modernization of the town began in 1975 and finished on 29 June 1979.
Today Năvodari is an important chemical and industrial town containing a chemical fertilizer factory, a factory for producing sugar, a car repairs factory and a Petromidia factory specialized in petrochemical products.
Năvodari has also developed in the social and cultural fields; in the city center there is a children's town, built between 1969 and 1972, vacation accommodations, and sports facilities where up to 12,000 visitors can be accommodated.
Some 5 kilometres from the town itself there is a summer camp (the largest one in Romania), built under the communist regime for school children. Due to its interesting programmes, good accommodation and acceptable prices, it was extremely popular among teachers and parents. In the early 2000s, it was opened for the public at large as a cheap seaside resort.