Polymer-modified cement mortars (PCM) and concretes (PCC) are mainly used in concrete repair and restoration exhibiting improved durability, suitable chemical resistance, and beneficial adhesion strength compared to unmodified cementitious materials. Due to these favorable properties, the material is increasingly implemented in construction. Commonly, the modifiers applied to cementitious binders consist of thermoplastic polymers, which feature a change in the deformation behavior under the influence of different temperatures. Despite the distinct temperature-dependent properties of the polymers, the load-dependent deformation behavior of PCM and PCC was barely investigated within a service temperature range. To make statements about the effect of polymers on the load bearing and elastic deformation behavior of PCM and PCC, the engineering properties of the material have to be experimentally assessed under thermal conditioning. Accordingly, the compressive and flexural strength as well as dynamic and static modulus of elasticity of seven different PCM mixtures were characterized while the specimens were exposed to service temperatures of −20 ℃, 20 ℃, and 60 ℃. After the specimens were thermally conditioned in a climate chamber, the samples were transferred to the equally conditioned test machine and tested in the proposed temperature scope. The experimental results reveal influential changes in all tested mechanical attributes for the modified system within the applied service temperature range compared to an unmodified reference. This knowledge is essential to further investigate the temperature impact on the material and develop appropriate prediction models for the application of polymer-modified cementitious materials in construction and the integration in design guidelines.