Mountain Pine Ridge Forest Reserve is a nature reserve in the Cayo District of southern central Belize. It was established in 1944 to protect and manage the native pine forest. Its boundaries are poorly defined, but it is estimated to cover an area of 106,352.5 acres (430 km²), although much of the reserve has been leased.
The reserve is predominantly pine forest (58.5%), primarily Honduras Pine, Pinus caribaea var. hondurensis, but with significant broadleaf forest (36.8%). There are small areas of grassland (3.4%) and wetland (0.6%). Roads, rivers and other features make up the remainder of the area (10.9%). The climate is subtropical with a rainy season from July to February. During the dry season (February to May) temperatures may reach 39 °C (102 °F) with a humidity level of 70%.
The majority of the reserve is situated on a granite massif, with some areas of limestone in the west of the reserve (remnants of a limestone plateau laid during the Jurassic). Sinkholes and caves are common in the limestone areas. The underlying soils are predominantly sandy. The elevation of the reserve averages between 400 and 700 m (1,312 to 2,296 ft) with the highest point being Baldy Beacon at 1,017 m (3,336 ft), and dropping to 120 m (394 ft) at the lowest point of the Macal River.
The Macal River forms the boundaries of the reserve to the west and south and is fed tributaries including Rio Frio, Rio On, Privassion Creek and Piviol Creek. To the north-east some small streams feed into Barton Creek.