The climate on Mount Pulag is tropical with rains predominating the whole year. Rainfall on the mountain averages 4,489 mm yearly with August being the wettest month with an average rainfall of 1,135 mm.
The mountain hosts 528 documented plant species. It is the natural habitat of the endemic dwarf bamboo, (Yushania niitakayamensis) and the Benguet pine (Pinus insularis). Among its native wildlife are 33 bird species and several threatened mammals such as Philippine deer, giant bushy-tailed cloud rat and long-haired fruit bat.
On February 20, 1987, a large part of the mountain is designated as a National Park with Proclamation No. 75. This aims to preserve the environment around the mountain due to threats from increased development such as conversion to agricultural lands, timber production, hunting, and increased tourism.
The indigenous people of Benguet consider the mountain to be a sacred place.