A numerical scheme was developed for calculating the inertial collection efficiencies of particles by elliptical fibers and filtration pressure drop. The viscous flow fields for single elliptical fiber were determined by solving the Navier-Stokes equation numerically, and the effects of the following parameters, such as orientation angle (θ), cross-section aspect ratio (ε) and packing density (C) on the filtering performance were discussed. The results showed that the filtration pressure drop for elliptical fibers increased with the increasing aspect ratio for large orientation angle but decreased for small orientation angle. With the same cross-section aspect ratio, the filtration pressure drop increased with the increasing orientation angle. The efficiency of elliptical fibers with larger orientation angle and cross-section aspect ratio was higher than that of circular fibers for intermediate and high-inertia particles, whereas for low-inertia particles, the elliptical fibers with small orientation angle showed higher collection efficiency. The quality factor, an indicator of the ratio of the collection efficiency to the pressure drop, was used to evaluate the comprehensive performance of the elliptical fibers. It was found that the elliptical fibers with large aspect ratios (i.e., long and slim elliptical fibers) showed higher the quality factor (i.e., better comprehensive filtration performance) in capturing intermediate and high-inertia particles when the orientation angle was about θ=45°. For low-inertia particles, the elliptical fibers with major axis parallel to the incoming flow might have filtration performance advantages.