The arbitrary Lagrangian-Eulerian technique was used in the direct numerical simulation of the sedimentation of particle with thermal convection between parallel walls. The fluid motion is computed from the Navier-Stokes equation and energy equation using the finite-element method. The particle was tracked according to the equations of motion of a rigid body under the action of gravity and hydrodynamic forces arising from the motion of the fluid, the model was used without former experience or presumption. The results shows that the particle experiences different regimes of motion: steady motion with and without overshoot and weak, strong and irregular oscillations. The thermal convection changes the sedimentation velocity and the oscillation amplitude of the particle，and the impact of particle by the thermal convection was decreased with solid-liquid density ratio increasing.