Flexible pressure sensors have received tremendous attention for various wearable applications. However, it remains a critical challenge to develop a flexible pressure sensor with excellent sensitivity performances and multiple advantageous properties. Herein, a high-performance flexible piezoresistive pressure sensor PMIA@PDA@Ag was developed, which sensitive component is consisted of Ag nanoparticles decorated polydopamine (PDA)-modified meta-aramid (poly(m-phenylene isophthalamide), PMIA) nanofibrous membrane. The PMIA@PDA@Ag pressure sensor shows excellent mechanical, thermal insulation, antibacterial and breathable properties, as well as remarkable sensing performances including high sensitivity, wide detectable pressure range, rapid response speed and good cyclic durability. In addition, it also shows great sensing performances in monitoring various human behaviors in real-time, including large-scale motions and subtle physiological signals.