Trees to 50 m tall; trunk to 1 m d.b.h.; bark gray-brown or gray, fissured longitudinally into irregularly oblong plates, inner bark red-brown; branchlets densely red-brown, occasionally yellow pubescent; winter buds reddish brown, oblong-ovoid, slightly resinous. Needles 5 per bundle, dark green, straight, almost triangular in cross section, 6-12 cm, stomatal lines 6-8 along each abaxial surface, blue-gray, vascular bundle 1, resin canals 3, median, base with sheath shed, margin serrulate. Seed cones solitary or several clustered near apex of 1st-year branchlets, erect, pedunculate (peduncle 1-1.5 cm), conical-ovoid or ovoid-oblong, 9-14 × 6-8 cm, indehiscent or slightly dehiscent at maturity, with seeds exposed but not shed. Seed scales reflexed at apex. Seeds triangular-obovoid, 1.2-1.6 cm, wingless.
In the Russian Far East this pine grows from 200 m to 600 m a.s.l., 500 m to 1,300 m a.s.l. in China, and in Japan it occurs to an altitude of 2,500 m. The climate has a summer monsoon character within proximity of the coast, but with a strong continental influence further inland. Temperature extremes range from +37 C to -45 C within its natural range. Pinus koraiensis grows in dry places on podzols among deciduous broad-leaved trees like oaks, poplars and birches, but on the Russian coast of the Sea of Japan it is codominant with Abies holophylla, forming groves of conifers in a more varied deciduous broad-leaved forest. In Japan it also occurs together with other pines. In Korea and NE China ('Manchuria') this pine has been heavily exploited, resulting in the disappearance of many magnificent pine forests.
Pinus koraiensis has a wide distribution in the Russian Far East, northeast China and North Korea. Smaller subpopulations also occur in South Korea and Japan. In the Russian Far East legal and illegal exploitation for its timber has resulted in a decline in its area of occupancy of up to 50% (CITES 2010). In China over-exploitation for its edible nuts and to a lesser extent, its timber is leading to forest degradation in some areas (Tang 2010). There is little species specific information about its status in North Korea although generalized reports into the state of the environment (UNEP 2003, Hayes 2009) and satellite based studies on deforestation in and around areas such as Changbaishan/ Baekdu-san Biosphere Reserves (Tang 2010) indicate that some decline is likely. In South Korea and Japan the small subpopulations are thought to be stable. Despite the continuing exploitation, this species' large distribution and (still) large overall population size means that it does not yet meet the requirements for any of the threatened categories or those for Near Threatened. This situation may change within the next decade should current trends continue.
Legal and illegal logging is reducing its area of occupancy. In Russia, it is estimated that its abundance has been reduced by up to 50% in the past two decades (CITES 2010). In northeastern China and North Korea over-exploitation for its edible seed (a valuable source of local incomes) has led to some forest degradation and a decline in forest health (Tang 2010). In northeastern China and South Korea natural forests and plantations have also been impacted by white pine blister rust (Zhang et al. 2010).
This species occurs in several protected areas within its wide range, but also outside such reserves. It is now listed on Appendix III of CITES in an attempt to control illegal logging. In November 2010 the Russian Government announced a ban on the logging of Pinus koraiensis in its territories in order to assist the conservation of the Tiger (Panthera tigris altaica) of which the pine forests are its key habitat.