Polylactic acid (PLA) and bamboo fiber are both green and biodegradable materials. However, the bonding of PLA and bamboo fiber is poor, which limits the physical properties of paper. The effects of polyvinyl alcohol (PVOH) on PLA fiber/bamboo fiber composites were studied by measuring the tensile strength, tear resistance, and breaking length of the paper. In addition, the morphology of paper comprised of PLA fiber and bamboo fiber were investigated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The tensile index, tear index, and breaking length of paper made with the 4 wt% PVOH-treated bamboo fiber and the untreated PLA fiber compared favorably with the paper made of the untreated bamboo fiber and PLA fiber increased 21.0%, 8.6%, and 20.8%, respectively. However, compared with the paper made of the untreated bamboo fiber and PLA fiber, the tensile index, tear index, and breaking length of the paper made with the treated PLA fiber and the treated bamboo fiber with 4 wt% PVOH solution were dramatically reduced by 30%, 18%, and 30%, respectively.