Multifilamentary Bi2Sr2CaCu2Ox (Bi2212) composite wires are the only high-temperature superconducting round wires (RWs) with sufficient critical current density (Jc) for superconducting magnets generating magnetic fields greater than 25 T. Previous works indicated that various voids in Bi2212 filaments and bridges between the adjacent Bi2212 filaments in Bi2212 RWs were generated after heat treatment. Such complicated microstructural structure will inevitably affect its electrical behavior. Previous studies only focus on single microstructural feature, voids or bridges. Hence, we developed a numerical model containing both voids and bridges to explore the comprehensive influence of these two microstructural features. Due to the preliminary results, it shows that the E-J relationships of the models with bridges and with infinity bridges are similar in the case of numerous bridges between filaments. It indicated that we can build a simplified geometry structural model by removing all the bridges and bonding the adjacent filaments directly. And then the parametric study of the voids was carried out and the results explained that the height (diameter) of void is the key factor to dominant its electrical behavior.