The morphology, mechanical properties, in vitro biocompatibility and fabrication of three-dimensional (3D) printing strips of composite materials containing polylactide (PLA) and Camellia oleifera fruit hull powder (COFHP) were evaluated. Acrylic acid-grafted polylactide (PLA-g-AA) and COFHP were used to enhance the desired characteristics of these composites. The PLA-g-AA/COFHP materials had better mechanical properties than the PLA/COFHP composites. This effect was attributed to a greater compatibility between the grafted polyester and COFHP. Additionally, the PLA-g-AA/COFHP composites provided higher quality 3D printing strips and were more easily processed because of ester formation. The water resistance of the PLA-g-AA/COFHP composites was greater than that of the PLA/COFHP ones, and in vitro biocompatibility evaluation with mouse tail-skin fibroblasts (FBs) indicated that both materials were nontoxic. Moreover, COFHP enhanced the antibacterial activity properties of the composites. Composites of PLA-g-AA or PLA containing COFHP had better antibacterial activity.