<p>The wire-arc hybrid additive/subtractive manufacturing is a promising processing technology, which is suitable for the manufacturing of large-sized complex components. However, the process characteristics of the hybrid manufacturing presents challenges for the process planning. To address these problems, this paper proposed a novel two-phase process planning method, which can improve the efficiency with considering the wire-arc based hybrid additive/subtractive manufacturing process characteristics. In the first stage, a tool reachability area correction algorithm is developed to evaluate the interference between the cutting tool and the formed area. The 0–1 integer programming model is constructed, and the initial additive/subtractive processing sequence can be obtained based on the manufacturability and processing efficiency. In the second phase, this paper quantifies the influence of thermal behavior on both the collapse height of components and the cooling time of materials during the additive manufacturing process. The decisions regarding the alternation of additive and subtractive processes can be made adaptively based on real-time monitoring of thermal conditions. Typical structures are selected for experimentation through the simulation and actual manufacturing, and that the proposed methodology can provide the reasonable hybrid additive/subtractive manufacturing scheme, which can effectively reduce manufacturing time and costs, while maintaining dimensional accuracy.</p>