First-principle calculations in the frame of density-functional theory (DFT) in the general gradient approximation (GGA) are performed by using the augmented plane wave plus local orbital (APW+lo) method for pure GaAs(110) surface and the adsorptions of Xe atoms on it. A supercell consisting of five atomic layers is constructed to simulate the geometical configuration of clean GaAs(110) surface and the adsorption of Xe atoms. The Newton dynamics method is used to relax the atomic positions. Initiating with the Xe atom on top of Ga atom, As atom, and at the bridge site, respectively, it is found that the total energy of the supercell reaches the minimum when the Xe atoms are located at the bridge site. Additionally, it is shown that the adsorption of Xe atoms make the relaxed GaAs(110) surface to return to the ideal crystal geometrical configuration as generally expected.