The poly(poly(ethylene glycol) methyl ether methacrylate)‐ (PPEGMA)‐grafted bamboo fiber (BF) (BF@PPEGMA) was successfully synthesized via the esterification and atom transfer radical polymerization (ATRP) methods. The poly(butylenes succinate) (PBS) matrix‐based composites including BF and BF@PPEGMA were prepared by a twin‐screw extruder. The structure, morphology, as well as the properties of BF@PPEGMA and composites was investigated. The results indicated that PPEGMA was successfully grafted onto the BF surfaces, making BF surfaces rough and less thermally stable. The BF@PPEGMA showed of stronger interactions with PBS matrix than pristine BF, leading to the improvement of tensile modulus, tensile strength, and elongation at break of the composites. The PBS/BF@PPEGMA composites absorbed less water than PBS/BF composites due to the existence of less content of hydroxyl groups after surface modification. Incorporation of BF and BF@PPEGMA facilitated the crystallization of PBS at higher temperatures, leading to formation of regular spherulites without appearance of transcrystallization. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.