In this work, a green, facile and efficient melt blending and supercritical CO2 foaming technology was proposed to fabricate biodegradable chain-extend poly (lactic acid) (CPLA)/poly (butylene adipate-co-terephthalate) (PBAT) blended foams with open-cell structures and selective oil adsorption characteristics. The residual epoxide group induced the formation of PLA-CE-PBAT in CPLA95/PBAT5, where PLA-CE-PBAT enhanced the melt strength and accelerated the crystallization of PLA. During the foaming process, CPLA and crystals acted as the hard phase, and PBAT served as the soft phase. As a result, open-cell CPLA95/PBAT5 blended foam possessed a high volume expansion ratio of 17.3 times and a high open-cell content of 96.4%. Furthermore, the adsorption capacity of open-cell CPLA95/PBAT5 blended foam for various solvents ranged from 3.8g/g to 11.2g/g, and it had excellent reusability. The fabricated open-cell CPLA/PBAT blended foam could achieve the original intention of selective oil adsorption characteristics with green and sustainable development.