Abstract: We addressed the elimination of environmental interference to single-electrode dielectric barrier discharge ion (DBDI) source.The original work was the wire-mesh screen, shielding DBDI source.The influence of the mesh-size (g) of wire-mesh screen on the behavior of DBDI low-temperature plasma plume (LTPP) was mathematically modeled, theoretically analyzed and numerically simulated.The simulated results show that the mesh-size has a major impact.For example, the wire-mesh screen with mesh-size of 0.5 mm increases the total metastable ions by 5.3 times, heightens the peak densities of He^* and N₂^* by 7.86 times and 2.31 times, respectively, and decreases the peak densities of other ions by over 3 times.As the mesh-size decreases from 0.7 to 0.3 mm, the proportion of metastable ions increases while their total number changes in an increase-decrease manner.We suggest that when it comes to background noises suppression, the optimized mesh-size be 0.3 mm ≤ g ≤ 0.4 mm.