Thermal expansion problems for unidirectional pultruded composite samples were studied. The composite materials were subjected to temperatures ranging from 0 to 200°C in order to simulate service conditions. A thermal-mechanical analyzer was employed for gathering experimental data, and the results were compared with those generated using the ANSYS software and micromechanical models. A finite-element analysis (FEA) by utilizing ANSYS was also carried out. The thermal behavior of pultruded jute-fiber-reinforced unsaturated polyester composites was simulated, and the results obtained were then compared with experimental data and predictions provided by several micromechanical models. It is found that the Schapery and Chamis micromechanical models are more efficient in predicting the value of CTE in the longitudinal and transverse directions, respectively.