<p>Fracture failure of body-centered cubic (BCC) lattice structures is a critical risk to their safe application in load-bearing lightweight components. To address the issue of evaluating the reliability of the BCC lattice structures, this paper proposes a novel reliability analysis model based on the serial system, where each strut in the BCC lattice is treated as an individual element for reliability analysis. First, to elucidate the failure mechanism, various parent specimens and BCC lattice specimens are fabricated and subjected to mechanical testing. Then, based on the found failure mechanism and introducing the material properties, the failure mode of the lattice structure is reconstructed as a series system, from which the overall reliability of the BCC lattice structure is quantified. The model predictions agree well with the experimental results, demonstrating the validity of the proposed analysis model. Based on the proposed model, further analysis shows that BCC lattices exhibit lower variability than the parent material and that improving material plasticity helps reduce the reliability dispersion of the lattice structure. This model provides a practical tool for reliability-based design and quality control of BCC lattice structures and can be readily extended to other lattice topologies.</p>