The Lower Middle Triassic Heweitan Group on the northeastern side of the Karakorum Ranges in Xinjiang,China,is interpreted as having been deposited in middle to outer deep-sea fan complex.The strata are composed of turbiditic sandstone that exhibit Tbe,Tbcde,Tcde and Tde Bomma sequences and mudstones.A moderately diverse and relatively abundant trace fossil community is found in the Group,consisting,at ichnospecific level,of eleven froms: Bergaueria sp.; Chondrites sp.; Cosmorhaphe lobata;Glockeria sp.; Gordia sp.; Helminthopsis sp.; Muensteria sp.; Palaeophycos striatus;P.tubularis;Spirophycos sp., Thalassinoides sp. and Zoophycos simple form.The trace fossil community occurred in the deep-sea fan does not fit simply into Seilacher’s deep-sea Nereites ichnofacies.Based on the co-occurring relation,three associations have been recognized.Association 1 contains Bergaueria sp., Muensteria sp., Palaeophycos striatus,Thalassinoides sp.Though they are typical shallow water types in Seilacher’s ichnofacies model,they occur in turbidited deposited in middle submarine fan herein.The host rock that does not have shallow water marks indicates that they had been formed below strom wave base.Association 2 consists of only Zoophycos. The analysis of its morphology and comparison to its modern analogues suggest that it was built in a well-oxygenzted substrate with a depth of as much as 2000m.Association 3 is mostly diverse,comprising typical deep water Nereites ichnofacies representatives,such as Cosmorhaphe lobata,Glockeria sp.and Chondrites sp.,and ichnofacies breaking forms of Palaeophycos tubularis,Gordia sp., Helminthopsis sp and Spirophycos sp.The ethological and ecological analyses suggest a probable water depthranging from 300m to 2000m,which is accordant to the conclusion deduced from lithological analysis.These three ichnofossil associations occurred vertically from 3/2 to 1,showing a upward decrease of waterdepth. Similar trace fossil suite had been found in the turbidites of same age at Yushu and Guoluo districts of Qinghai Province,which indicates that there probably was a wide ocean to the north of the Qiangtang Micro-contient.