Abstract: The Jurassic marine trace fossil described has been found for the first time from the Upper Jurassic Yunshan Formation, County, Mishan Eastern Heilongjiang. It is a new trace fossil genus occurring at the Upper surface of a black mud—stone. The new trace fossil genus Mishanichnus is described below: Ichnus showing long,simple sinuous, width of trail 4 to lo mm., both sides not smooth, but border cleared quite. Median consisted of numerous meniscus ribs ranged by different interval. No branching.