Bergrivier Municipality (Afrikaans: Bergrivier Munisipaliteit) is a local municipality in the Western Cape province of South Africa. It governs the towns of Piketberg (the seat of the municipal council), Velddrif and Porterville, as well as the surrounding villages and rural areas. As of 2011^[update], it had a population of 61,897. It is located within the West Coast District Municipality and its municipality code is WC013.

The municipality covers an area of 4,407 square kilometres (1,702 sq mi) stretching from the Atlantic Ocean in the west to the Groot Winterhoek Mountains in the east. Much of its southern border follows the Berg River, while to the north it stretches as far as the Olifants River Mountains. The Piketberg mountain occupies the middle of the area. To the north it abuts on the Cederberg Municipality, to the east the Witzenberg Municipality, and to the south the Drakenstein, Swartland and Saldanha Bay Municipalities.

At the time of the 2022 South African Census, the Bergrivier municipality had a population of 70,276, an increase of 11.74% from 2011. 72.8% of the population identified as "Coloured," 15.4% as "White," and 10.3% as "Black African."

According to the 2011 census the municipality has a population of 61,897 people in 16,275 households. Of this population, 70.9% describe themselves as "Coloured", 16.9% as "White", and 11.3% as "Black African". The first language of 90.7% of the population is Afrikaans, while 3.8% speak Xhosa and 2.5% speak English.

The municipal headquarters are in the town of Piketberg, which is situated slightly north of the Berg River on the eastern slope of the mountain also known as the Piketberg. According to the 2011 census, Piketberg has a population of 12,075. The other principal towns in the municipality are Velddrif (pop. 11,017) on the Atlantic coast at the mouth of the Berg River, and Porterville (pop. 7,057) on the edge of the Groot Winterhoek Mountains.

There are smaller agricultural villages in the vicinity of Piketberg at Goedverwacht (pop. 1,979) and Wittewater (pop. 848), and in the northern parts of the municipality at Aurora (pop. 578), Eendekuil (pop. 1,530), and Redelinghuys (pop. 574). Dwarskersbos (pop. 670) is a fishing village and coastal resort near Velddrif.

At the end of the apartheid era, in the area that is today the Bergrivier Municipality there were municipal councils for Piketberg, Velddrif, Porterville, Eendekuil, Aurora, and Redelinghuys. These councils were elected by the white residents, while the coloured residents of the towns were governed by management committees subordinate to the white councils. Dwarskersbos was governed by a local council, and the remaining rural areas were served by the West Coast Regional Services Council.

While the negotiations to end apartheid were taking place a process was established for local authorities to negotiate voluntary mergers. Some towns in the Bergrivier took part in this process, which resulted in the municipalities merging with their respective management committees to form new non-racial municipalities: Piketberg and Aurora in August 1992, and Eendekuil in January 1993.