Polylactic acid (PLA) is one of the most suitable candidates for environmental pollution treatment because of its biodegradability which will not cause secondary pollution to the environment after application. However, there is still a lack of a green and facile way to prepare PLA oil-water separation materials. In this work, a water-assisted thermally induced phase separation method for the preparation of superhydrophobic PLA oil-water separation material with honeycomb-like structures is reported. The PLA material shows great ability in application and could adsorb 27.3 times oil to its own weight. In addition, it could also be applicated as afilter with excellent efficiency (50.9 m3 m-2 h-1).