The wiring of high-speed optoelectronic three-dimensional (3D) integrated systems features a high density, small size, and complex structure. Accurate characterization of vertical through-silicon via (TSV) structures in high-speed optoelectronic 3D integration can significantly improve system reliability while reducing development time and tape-out costs. In this study, a high-speed coaxial TSV structure with various parameters was simulated. Next, based on the geometrical and process parameters determined from the simulation, a proper high-speed coaxial TSV test structure based on the L-2L de-embedding method was designed and fabricated on an eight-inch process platform. Finally, the transmission characteristics of the high-speed TSV were obtained through de-embedding. A comparison between the test and simulation results reveals an average error of 0.938% between them within 40 GHz. This result confirms the high accuracy of the simulation method, corroborating the feasibility of its application to high-speed TSV development and high-speed optoelectronic 3D integrated system design.