This study aims to delineate the biomechanical responses in both soft and hard tissues, alongside the interactions within the surrounding bone of a human skull subjected to clinical loadings generated by a miniscrew-assisted rapid palatal expansion (MARPE) device. Cone-beam computed tomography (CBCT) scans of a 20-year-old female skull were segmented. The skull bones were meticulously modeled to reconstruct a comprehensive 3D model for finite-element analysis (FEA). A displacement of 0.125 mm was applied on each side (0.25 mm total) of the MARPE device to simulate one complete turn of the jackscrew. The outcomes revealed that the miniscrews experienced a maximum equivalent von Mises stress of 264.91 MPa. Notably, the separation of the midpalatal suture exhibited a quasi-parallel deformation with an average displacement of 0.247 mm and a standard deviation of 0.00667 mm. The ratio of the rotational angle to the lateral displacement of the zygomaticomaxillary complex was 0.6436 degree/mm. No Fracture of miniscrews was observed during the activation of one turn per day.