<p>This study investigates the influence of non-local thermal stresses on the mechanical behavior of fiber-reinforced poro-viscoelastic structures, utilizing the Lord-Shulman (L–S) model to incorporate thermal relaxation effects. The research employs normal mode analysis to derive and analyze the governing equations and boundary conditions, which integrate the Lord-Shulman heat conduction law and constitutive relations for viscoelastic porous materials. The study explores the effects of key parameters, such as relaxation time, porosity, and viscoelastic properties, on heat propagation and the thermo-mechanical response of the structures. Analytical solutions for the governing equations are obtained through normal mode analysis, yielding explicit expressions for critical physical quantities, including stress components, displacements, and temperature distributions within the material domain. These analytical results are then numerically evaluated for a specific material, with the findings presented graphically to illustrate the influence of the studied parameters. Additionally, the predictions of the Lord-Shulman (L–S) theory are compared with those of the classical heat conduction (C–T) theory, both in the absence and presence of viscous parameters, highlighting the differences and implications of the two approaches. This work provides valuable insights into the thermo-mechanical behavior of fiber-reinforced poro-viscoelastic structures under non-local thermal stresses.</p>