A new steady-state voltage coordinated control strategy for a UHVDC/AC power system with a large-scale synchronous condenser is proposed. First, the relationship between steady output and dynamic voltage support capability of the synchronous condenser is studied, and then a determination method of its steady reactive power in the premise of solidly guaranteeing the support capacity of condenser transient voltage is presented. On this basis, the coordinate control strategy of UHVDC station reactive power compensation equipment and Automatic Voltage Control (AVC) of neighborhood power grid with the participation of large capacity condenser is presented. Based on the EPRI-36 node system, the control effects of three control modes, including UHVDC converter station and AVC of neighbor regional power grid controlled separately, coordinate control between UHVDC and neighbor power grid, coordinate control between large-scale synchronous condenser, UHVDC and neighbor power grid, are simulated and analyzed in the situations of operational variation of the UHVDC and reactive power variation of a neighboring power grid. The simulation results prove the superiority and feasibility of the proposed control strategy. This work is supported by National Natural Science Foundation of China (No. 51837004).