A novel synthesis strategy for hierarchical polypyrrole nanopillar/silver nanoparticle arrays is designed and its application as an antibacterial surface and nonenzymatic H2O2 sensor is explored. The hierarchical structure is fabricated using a microporous membrane‐templated method by multiple steps. Using a polypyrrole nanopillar array as the matrix, silver nanoparticles can be uniformly reduced and stably anchored onto the nanopillar array by a redox reaction in a AgNO3 solution. The morphology, structural characteristics, conductivity, and reaction mechanisms of the composites are studied in detail. The incorporation of Ag nanoparticles not only significantly enhanced the antibacterial activity of the surface, but also contributed to the excellent ability to detect H2O2. This work provides a versatile approach to achieve the controlled fabrication of hierarchical metal‐conducting polymer composite structures and demonstrates them as promising multifunctional interfaces with antibacterial and sensing activity.