<p>This study analytically investigates the deformation behavior of an isotropic photothermoelastic moisture plate subjected to coupled thermomechanical loading within the framework of the multi-temperature theory. The governing two-dimensional equations for such a plate are formulated, and suitable potential functions are introduced to enhance analytical tractability and enable partial decoupling of the system. To facilitate solution development, the equations are expressed in a non-dimensional form, after which Laplace and Fourier transform methods are applied to derive the solutions in the transform domain. The model is then analyzed under the influence of a normal force and an external thermal source. The transformed solutions provide a range of field quantities, including displacements, stresses, temperature variation, carrier density distribution, and moisture concentration. Validation of the model is carried out through detailed calculations for a specific material, and numerical results are illustrated graphically to capture the effects of multi-temperature interactions under thermomechanical excitation. The outcomes of this study have promising implications for the design and optimization of semiconductor devices, and other engineering applications where the interplay of thermal, plasma, moisture, and multi-temperature effects is significant.</p>