The Bío Bío province is in the southeast of the Bío Bío region with an area of 14,987.9 sq mi (38,818 km2). It is the only province of the region that is not along the coast. The capital, Los Ángeles, is to the southeast of Concepción, the capital of the region.
Bío Bío is bordered to the north by the Ñuble province, to the west by the Concepción province, to the east by Argentina, to the south by the Araucanía region and to the southwest by the Arauco province
The main river that flows through the province is the Bío Bío.
The climate of Los Ángeles is a Mediterranean climate, Cfb in the Köppen climate classification.
The average amount of precipitation for the year in Los Ángeles is 1,069.3 mm (42.1 in). The month with the most precipitation on average is May with 254 mm (10.0 in) of precipitation. The month with the least precipitation on average is February with an average of 15.2 mm (0.6 in).
The average temperature for the year in Los Ángeles is 13.9 °C (57.0 °F). The warmest month, on average, is January with an average temperature of 20 °C (68 °F). The coolest month on average is July, with an average temperature of 7.8 °C (46.0 °F).