Currently available nasal filters are not well-suited to protect against the fine and ultrafine airborne particles. In this research, we designed and evaluated a novel nanofiber nasal filter (NNF) capable of reducing personal exposures not only to large allergenic particles but also to ultrafine particles, thus reducing respiratory health risks. A new hybrid filter (HF) medium for the NNF was fabricated by overlaying a carbon filter substrate with nylon nanofibers produced by electrospinning. After optimizing filter’s production parameters, the HF was produced from the nylon-6 polymer solution with the concentration of 15 wt%, a substrate based on MERV 5 carbon filter with 61 kg m–3 density, and the nanofiber surface coating density of 0.72 g m–2 (or 0.54 g m–2 as a second choice). The new HF was tested with fluorescent polystyrene latex beads of 0.026–3.1 µm in size and at 7.5–30 L min–1 operating flow rates. The newly developed NNF showed more than 90% collection efficiency for particles >1 µm representing bacteria and molds and > 50% for particles < 0.5 µm, including ultrafine particles – about 2.3× improvement compared to commercially available nasal filters. The NNF could serve as a useful tool to minimize our exposures to airborne pollutants.