<p>Part sedimentation in volumetric additive manufacturing (VAM) technology is a well-known detrimental effect that can significantly deteriorate printing resolution and shape fidelity. This study reveals the underlying mechanism by which process parameters and material properties affect the sedimentation properties of parts fabricated by VAM, considering the intrinsic thermal process and its interaction with polymerization kinetics. It was found that thermally induced changes in material viscosity and polymerization parameters played an essential role in regulating sedimentation behavior. Lowering the ambient and initial printing temperatures can increase viscosity resistance and thus weaken the sedimentation phenomenon, whereas a longer printing time adversely influences part sinking. Optimal thermal conditions that simultaneously ensure low sedimentation and a relatively short printing time should be determined during printing, particularly for thermally thinned materials. Importantly, using the wall-end effect, the model revealed that settlement could be effectively mitigated by solidifying the part near the bottom of the container. The experiments confirmed a reduction of approximately 39.4% in sedimentation displacement. The thermal-solid-fluid coupled model developed in this study offers a valuable tool to guide the design of new photosensitive materials as well as the optimization of process parameters, which is essential to improve the printing outcomes of VAM and thus facilitate its broader applications.</p>