The preparation of Janus nanofibers by electrospinning using a side-by-side needle is a well-known method. In this study, a new method was developed that utilized the phase separation phenomenon in a mixed solution of polycaprolactone (PCL) and polyvinylpyrrolidone (PVP) to prepare Janus nanocomposites via electrospinning. The morphology, hydrophilicity, and pore size distribution of the PCL/PVP Janus nanofibers were investigated. The results showed that the best effect was obtained when the PCL to PVP mass ratio was 1:1. In order to further verify that the method could successfully prepare nanofibers with the Janus structure, Ag nanoparticles (AgNP) were loaded on the nanofibers, which gave them an antibacterial property. The distribution of the AgNP on the nanofibers could be observed using transmission electron microscopy. (C) 2019 Elsevier B.V. All rights reserved.