Pinirhiza alba, is described as a new ectomycorrhiza associated with Pinus roxburghii from Pakistan. The mycorrhiza is characterized by milky white mycorrhizal systems, dichotomous b ranching pattern, thick plectenchymatous to pseudoparenchymatous mantle and loosely woven hyphae of uniform diameter forming rhizomorph. As so far no fungal partner of this ectomycorrhyza has been identified, hence it falls under the category of unknown mycorrhizae.