Steam exploded bamboo (SEB) fibers were treated with alkali solution to remove lignin and hemicelluloses and also to increase the compatibility with biodegradable matrix resin. The fibers were processed by simple hand-lay-up method and hot pressed using dispersion-type biodegradable poly lactic acid (PLA) resin to produce a PLA/bamboo fiber cross-ply (0/90)s laminate composites, whose fiber content varied from 17 up to 68 wt.%. The intermolecular interaction among bamboo fiber and PLA matrix was discussed based on Fourier transform infrared (FTIR) analysis. The results showed that the tensile strength of alkali treated bamboo fiber was comparable with those of common strong natural fibers such as hemp and flax fibers. The composites' strength was similar to that of ordinary glass fiber-reinforced plastics laminate and the specific strength was three times higher than that of mild steel. It was also found that the cross-ply (0/90)s SEB/PLA laminate has the same cracking character as the common cross-ply laminates based on carbon or glass fibers.