This study investigates vortex-induced vibrations (VIVs) on dual parallel suspenders using wind tunnel experiments and employs a two-degree-of-freedom setup for each circular cylinder to closely simulate actual structural conditions. The VIV responses of dual cylinders exhibit notable deviations and complexity due to aerodynamic interaction. Results indicate a significant shift in the VIV lock-in range towards higher values for dual cylinders, compared to single ones. Both upstream and downstream cylinders demonstrate lower maximum VIV amplitudes than the single-cylinder. The cylinders exhibit effects of negative aerodynamic damping within the VIV process, with the aerodynamic damping becoming more pronounced as amplitude increases. Additionally, the time-dependent phase relationship between the cylinders contributes to these variations in response. Further analysis of surface wind pressure distribution reveals that aerodynamic interference in dual-cylinder systems leads to intricate pressure patterns and modal behaviors.