This is the first report to Trichodon cylindricus var. oblongus in China, and the genus Trichodon to the Xinjiang Uygur Autonomous Region. The study showed that: (1) the variety is characterized by the leaves widespreading when moist, with a broad and sheathing base, rather abruptly narrowed to a long, linear subula, plane margins, costa filling most of the subula, rough at back, a stereid band on abaxial of guide cells, leaf cells rectangular to shortrectangular; tubers on rhizoids; ellipsoidal capsule slightly curved, with linearlanceolate segments divided into two nearly to base. (2) There are three taxa of Trichodon in China up to now. T. cylindricus var. oblongus can be easily separated to var. cylindricus by shorter seta and capsule. T. cylindricus var. oblongus is characterized by the tuber present, leaf with sheathing base, plane margins, while T. muricatus Herzog is characterized by tuber absent, leaf with slightly sheathing base, recurved margins. (3) In Ditrichaceae, many genera have stereid band on both adaxial and abaxial sides of guide cells. Just genus Trichodon has stereid band differentiate only on abaxial side. T. cylindricus var. oblongus has squarrose leaves versus other genera of Ditrichaceae have erect leaves or nearly so. It has leaf with sheathing base, smooth capsule when dry, and incurved segments of peristome versus the genus Ditrichum has leaf without sheathing base, strongly furrowed capsule when dry, and straight segments of peristome. (4) Trichodon cylindricus var. oblongus is a dispersed type to arcticalpine. It is a disjunctly distributed species on EuropeAsiaNorth America continent. The taxon may be viewed as an indicator in research for climate change and the transformation between sea and continent.