Composite of polyethylene oxide (PEO)/nitrogen-containing bacterial cellulose nanowhiskers (N-BCNWs) were prepared using an electrospinning method and compared to electrospun PEO and composite of PEO/bacterial cellulose nanowhiskers (BCNWs). N-BCNWs were prepared by plasma treatment of BCNWs using a microwave oven, after which the presence of nitrogen-containing functional groups (2.74%) on their surface was confirmed. The diameter of the electrospun PEO/N-BCNWs was smaller than that of PEO/BCNWs composite nanofibers with the same PEO and BCNW concentrations. The weight losses, melting temperature and crystallization temperature of PEO/N-BCNWs were also lower than those of the other electrospun samples. These results show that the nitrogen-functionalized BCNWs used as a filler in the PEO polymer are suitable for application in humidity sensor and biomedical fields.