Abstract: The interface of the bamboo fibers/polylactic acid was controlled by alkali(NaOH) treatment, isocyanate (MDI) treatment and NaOH+MDI treatment, respectively. The results show that the NaOH treatment could further refine bamboo fibers and increase specific surface area, realizing the physical control of bamboo fibers/polylactic acid composites interface; MDI treatment could realize the chemical control of bamboo fibers/polylactic acid composites interface. All of the three kinds of the interface control methods could improve the mechanical properties of bamboo fibers/polylactic acid composites, among which NaOH+MDI treatment has the best positive effects on the interface properties of the composites, the tensile strength and impact strength of the bamboofibers/polylactic acid composites with interface control are increased 36.9% and 36.5%, respectively.