研究了高锰奥氏体钢在７７Ｋ下的抗拉性能、形变组织和断裂特点。研究表明，随氮含量的提高，抗拉强度呈线性增大。氮含量较高时，塑性下降。拉伸形变滑移带间夹角为４５～８０°，有一些滑移呈正三角形特征，符合奥氏体晶体学关系。较高氮含量合金拉伸断口上出现｛１１１｝＿γ穿晶刻面，刻面上有相交成６０°角的塑变滑移带。 The tensile properties, deformation microstructure and fracture characteristics of high manganese austenitic steels at 77K were studied. The research shows that with the increase of nitrogen content, the tensile strength increases linearly. When the nitrogen content is higher, the plasticity decreases. The angle between tensile and deformation slip bands is 45 ~ 80 °, and some slip features are equilateral triangle, which accords with the relationship between austenite and crystallography. The {111} _γ transgranular facets appear on the tensile fracture surface of the higher nitrogen content alloy, and there are plastic deformation slip bands on the facets which intersect at a 60 ° angle.