High throughput materials fabrication and characterization techniques are key to the transformation from materials genome approach to advanced materials R&D and manufacturing practice. Here the authors reported the application of the terahertz (THz-TDS) mapping of the electrical conductance of Cu alloy sample matrix fabricated using high throughput solid state synthesis method. Fast detection of 144 Cu alloy thin films on a single materials library chip were achieved. The mapping technique was based on an algorithm derived from Tinkham equations and Fresnel formula. The THz conductance acquired from alloy thin films of either uniform or continuous gradient thickness agreed semi-quantitatively with those determined with four-probe method. Distinctive conductance differences among the 144 Cu alloy samples were obtained within one batch. Further analysis of the changing trends in the microstructures and semi-quantitative compositions of representative samples against their electrical conductance revealed a clear composition-structural-function relationship. This study demonstrated that THz-TDS may be a powerful tool for fast high throughput screening of Cu alloy materials library chip, and facilitate the R&D procedure substantially.