The mechanical properties of poly(butylene succinate) (PBS) were significantly enhanced by compounding celluloseacetate (CA) nanofibers (CA-NF) to form CA/PBS composites. PBS has a great potential as an alternative material to other widely-used polyolefins such as polyethylene and polypropylene made from petroleum. PBS is especially well-known for its biodegradability, but the mechanical property of PBS was not sufficient as a commercial product for industrial applications. In this study, in order to enhance the mechanical property of PBS, a nanofiber made of CA was selected as a reinforcing material for the PBS composite. CA-NF were successfully synthesized using the 20 wt % CA solution with acetone/N, N-dimethylformamide (6/4 wt/wt) by electrospinning. The CA/PBS composites were then fabricated by mixing aligned or non-aligned (random) CA-NF. The highly oriented CA-NF were obtained using a rotating collector at the rotating speed of 430 m/min. The cross-sectional micrographs of the CA/PBS composites indicated that the electrospun CA-NF had good compatibility with the PBS matrix. The mechanical properties of the CA/PBS composites were investigated by tensile testing. It was found that the Young's moduli of the composites with the aligned CA-NF were higher than those of the composites with the random CA-NF. (C) 2017 Wiley Periodicals, Inc.