This paper focuses on a kind of metal cylinder, which has artificial microstructures of periodic subwavelength grooves on the surface, works in the terahertz band, and has been studied extensively. Losses are introduced into some of the grooves to examine the influence of the material loss on the scattering properties of metal microstructure cylinders. The results reveal that at a specific frequency, the absorption cross-section of the overall metal microstructure cylinder remains almost zero regardless of how the loss changes. The analysis of scattered field distributions and eigenmodes demonstrates that this loss-independent anomalous scattering is due to the loss-free bound state of the microstructure caused by symmetry breaking. The electric fields of this bound state are mainly distributed in the loss-free grooves, whereas almost no electric field is observed in the lossy grooves. This study provides a new method for designing high-performance photonic devices based on lossy metal microstructure cylinders.