Berazategui, partido (county) at the southeastern limits of Gran (Greater) Buenos Aires, eastern Argentina, in Buenos Aires provincia (province). It lies along the Río de la Plata estuary.
The county was created in October 1960 out of the existing county of Quilmes. Berazategui was originally the property of the Barragán family when it was sold in 1860 to José Clemente Berazategui and Juan Etcheverry. They established a colony of cattle ranchers on the land; the first meatpacking plant was built there in 1890, and beef has been an important product since that time. In 1906 Gaston Fourvel Rigolleau established a glass factory in Berazategui, and further industrial and commercial development followed. The area is also a textile centre; its first yarn-making industry was established in 1936. Pop. (2001) 286,735; (2010) 324,244.