Digital fabrication allows users to produce physical objects from digital models. However, conventional fabrication processes are mostly irreversible: once an object is fabricated, it is detached from its original virtual model and cannot be physically changed. In this work, we propose WireTruss, a novel approach for rapid prototyping truss mesh structures, which can be rapidly fabricated, easily assembled and manually modified to support an intuitive design iteration. We developed a parametric design tool that first simplifies the object into a truss graph composed of multi-way joints, and then calculates the route of the wire which is inherently a Euler path. Furthermore, WireTruss can be demonstrated its practical usability through a series of application cases.