Low temperature has a serious impact on crop yield, and cold acclimation can enhance the tolerance of winter wheat to adapte the changing climatic conditions. Thinopyrum intermedium (6X=42,StStJJJVSJVS) is one of the earliest species of Thinopyrum that was successfully hybridized with wheat, which contains excellent genes resistant to biological and abiotic stress, and provides many useful genes for wheat breeding. In this study, we selected a Tritelytrigia material 4-15-12 that could be servived in Harbin (-20℃) with outstanding agronomic traits, using the winter natural cold conditions in Harbin to screen high generation materials derived from a composite cross between Dongnong 024, octoploid tritelytrigia and Th.intermedium. The analysis results from morphological and molecular cytogenetic characterization showed that 4-15-12 was strong cold resistance and had disease resistance, lodging resistance and post-harvest of regrowth after maturity. Although the 1000-grain weight was only 23.82 g, the protein content was up to 18.67%. McGISH analysis showed that 4-15-12 had 56 chromosomes in the somatic cell of the root tip, and the chromosome set was composed of 42 and 14 chromosomes derived from common wheat and Thinopyrum, respectively. A total of 14 wheat alien chromosomes were 4 St-chromosomes, 6 Jvs-chromosomes, 2 Js-chromosomes, and 2 St/Jvs translocated chromosomes. The new germplasm of cold resistant Tritelytrigia accessions selected and identified in this study may provide a material basis for breeding cold tolerant wheat in high cold regions, as well as a new choice for the mining and accurate location of cold resistant genes.