Abstract: By reprocessing the previous gravity and magnetic data, the paper gains a new understanding about the NW structures in Northeast China, which was ignored or less attended before. It is thought that such structures not only exist in large numbers, but also play important roles in the geotectonic framework and mineral resources distribution in the region. Based on the discussion of the NW-trending characteristics of gravity magnetic field and geological stress conditions, the structures prove to be a set of independent tectonic system later than NE and NNE structures.