The Jeffrey Pine, Pinus jeffreyi (Washo: madá:š dewdíʔiš ), named in honor of its botanist documenter John Jeffrey, is a North American pine related to Ponderosa Pine.

Pinus jeffreyi occurs from southwest Oregon south through much of California (mainly in the Sierra Nevada), to northern Baja California in Mexico. It is a high altitude species; in the north of its range, it grows widely at 1,500 to 2,100 m (4,900 to 6,900 ft) altitude, and at 1,800 to 2,900 m (5,900 to 9,500 ft) in the south of its range.

Jeffrey Pine is tolerant of serpentine soils, and is often dominant in these conditions, even on dry sites at fairly low altitude. On other soils, it only becomes dominant at higher altitudes where the usually faster-growing Ponderosa Pine does not thrive.

The Jeffrey Pine is a large tree, reaching 25 to 40 m (82 to 130 ft) tall, rarely up to 53 m (174 ft) tall, though smaller when growing at or near tree line. The leaves are needle-like, in bundles of three, stout, glaucous gray-green, 12 to 23 cm (4.7 to 9.1 in) long. The cones are 12 to 24 cm (4.7 to 9.4 in) long, dark purple when immature, ripening pale brown, with thinly woody scales bearing a short, sharp inward-pointing barb. The seeds are 10 to 12 mm (0.39 to 0.47 in) long, with a large (15 to 25 mm (0.59 to 0.98 in)) wing.