Fiber reinforced polymer (FRP) composites, known for their high strength-to-weight ratio, are crucial for aircraft structures. To enhance their functionality beyond mechanical properties, these laminates are embedded with carbon-based nanomaterials such as CNTs, rGO, and GNPs. This addition grants them piezoresistive capabilities, transforming them into multifunctional laminates for structural health monitoring (SHM) applications. They have the potential to replace conventional sensors. Such a development is crucial to overcome limitations of conventional sensors, including limited temperature and sensitivity ranges, weight addition, manufacturing complexity, and the risk of introducing crack sites. Investigating the thermo-mechanical and piezoresistive behavior of multifunctional composites is essential to understand their ability to detect damage and failure across various temperatures and loading conditions. In this study, glass fiber reinforced polymer composite laminates were manufactured using the vacuum assisted resin transfer molding (VARTM) process. Reduced graphene oxide (rGO)-coated glass fabric, created via the dip-coating technique and acting as a sensor, was embedded in the laminate’s mid-plane. To evaluate the temperature-dependent piezoresistive behavior, in-plane tensile tests were carried out at two different temperatures with a constant displacement rate. The tests involve heating the sample until they reach an isothermal state, in which the load is then applied. Throughout the process, resistance changes are measured, and the gauge factor at each temperature was obtained. This study shows that as temperature increases, both resistance and stress decrease. Understanding this behavior is crucial for predicting the performance and durability of these materials in real-world conditions.