Human breast cancer tissue may have more than 2,000 metabolites.In order to distinguish the cancer grades, both qualitative and quantitative analysis of those metabolites are critical.Comprehensive 2D GC (GC x GC) is the only technology so far that can provide the separation power needed for this analysis.GCxGC is an advanced technology for chemical separations that provides significant improvements over traditional one-dimensional gas chromatography (GC), including an order-of-magnitude increase in chemical separation capacity, multidimensional ordering by chemical properties, and a significant increase in signal-to-noise ratio [1, 2].Coupling the GC×GC to a high speed time-of-flight mass spectrometer (TOFMS), yields an increase in information over a GC×GC-FID instrument, thus making the GC×GC-TOFMS more ideal to study complex samples.GC×GC x TOFMS instrumentation provides a third dimension of data that allows the analyst to more readily distinguish compounds[3].Here, we report a method using Zoex novel high resolution and high speed FasTOF TM GC x GC x TOFMS system for both qualitative and quantitative analysis of human breast cancer tissue samples.