Objectives : Degenerative arthritis arises from several physiological factors. The purpose of this study is to investigate the beneficial effects of Phyto-extract Complex (CME) on degenerative arthritis. Methods : CME is composed of extracts of mulberry (Morus alba L.) fruit, mulberry leaves and black beans (Glycine max (L.) Merr.). To measure the toxicity of CME, we performed the single-dose toxicity study. For the evaluation of its effects on degenerative arthritis, we examined the inhibition of cyclooxygenase-2 (COX-2) activity, using in vitro enzyme activity assay, the reduction of protein expression of COX-2, 5-lipoxygenase (5-LO), and inducible nitric oxide synthase (iNOS) in RAW264.7 cells which were stimulated by lipopolysaccharide (LPS). We also examined the serum level of prostaglandins (PGs) and injury of the knee joint cartilage, using animal model of degenerative arthritis induced by mono-sodium iodoacetate (MIA). Results : CME did not have any toxicity in single-dose toxicity study. The CME inhibited the activity of COX-2 and could reduce the protein expression of COX-2, 5-LO and iNOS in RAW264.7 cells. The CME also reduced the serum level of PGs and prevented from the cartilage injury of knee joint in animal model of degenerative arthritis induced by MIA. Conclusions : Taken altogether, the CME could be useful for the improvement of degenerative arthritis through its various anti-inflammatory activities and prevention from the cartilage injury of knee joint.