We investigated the effect of a novel porous scaffold composed with water-soluble poly(L-glutamic acid) (PLGA) and chitosan (CS) on the attachment, proliferation, and adipogenic differentiation of human adipose tissue-derived adult stem cells (ADSCs) in vitro and in vivo. Scanning electron microscope and fluorescent Dil labeling were used to reveal the attachment and growth of ADSCs on scaffolds; cell proliferation was detected by DNA assay. The adipogenic differentiation potential of ADSCs on the scaffolds was assayed by Oil-red O staining and further confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) for adipogenic gene markers (peroxisome proliferator-activated receptor γ2, lipoprotein lipase, fatty acid-binding protein, adiponectin). Cell-seeded constructs exposed to adipogenic medium for 2 weeks in vitro were implanted in severe combined immunodeficient (SCID) mice for 6 weeks. It was shown that ADSCs attached and spread well on scaffolds with good proliferation behaviors and abundance of extracellular matrix deposition. Oil-red O staining and RT-PCR showed adipogenic differentiation potential of ADSCs on scaffolds. Newly formed adipose-like tissue was confirmed in vivo in SCID mice by Oil-red O staining. PLGA/CS porous scaffolds exhibit good compatibility to ADSCs and can be promising biomaterials for adipose tissue engineering. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 101B: 68–75, 2013.