The increasing demand for data transmission bandwidth and energy efficiency driven by artificial intelligence and high-performance computing highlights the limitations of conventional copper interconnect technology, such as signal attenuation, high power consumption, and significant delays. Co-packaged optics technology achieves heterogeneous integration of photonic integrated circuits and electronic integrated circuits, providing a novel approach to overcoming the bottlenecks of electrical interconnects. The critical role of glass substrates as interposers in co-packaged optics technology is systematically analyzed, and the advantages of low dielectric loss, high thermal stability, wide spectral transparency, and compatibility with optical waveguide fabrication processes are illustrated. Discussions are provided on the ion-exchange technique for fabricating optical waveguides on glass substrates, the design of integrated electro-optical architectures, and representative schemes proposed by leading research institutions. In addition, challenges related to manufacturing yield, thermal management, and standardization coordination in glass substrate co-packaged optics technology are evaluated, and potential applications in data centers and related fields are projected.