The synergistic effects were observed on inhibiting alpha-glucosidase activity between Dendrobium and Pueraria thomsonii form self-made chewable tablets by taking the acarbose as control. Drosophila melanogaster was used as experimental animal, and the model of Ⅱ diabetic Drosophila melanogaster was prepared by high glucose and high fat feeding. The experiment was divided into model control group, positive control group, Dendrobium (D) group, Pueraria thomsonii (PT) group and (Dendrobium + Pueraria thomsonii) (D+PT) group. After 7 days of lipid-lowering effects between Dendrobium and Pueraria thomsonii was analyzed. results showed that all of groups dose-effect perfusion, the total protein, triglycerides and trehalose content were measured. Compared with control group, the influence of experiments on glycolipid metabolism in Dro-sophila melanogaster was researched, respectively. Furthermore, the Dendrobium and Pueraria thomsonii showed synergistic relationship on inhibition of alpha-glucosidase activity. The results showed that each groups of water extract and alcohol extract played a certain role in inhibition of alpha-glucosidase activity with dose-effect relationship, and the ranking of inhibition effect of water extract groups was acarbose ＞ D ＞ (D+PT) ＞ PT, and among which D group showed strongest effect while PT group was the strongest in the alcohol extract. Therefore, D and PT had no synergistic effects in vitro. It was found that D group, PT group and (D+PT) group had the effect of triglycerides and trehalose lowering, but had no significant effect on total protein content (P＞0.05) . Compared to the model group, the the (D+PT) group hand the best effect on lowing triglycerides (P＜0.05) and trehalose (P＜0.01). It is indicated that Dendrobium and Pueraria thomsonii had synergistic effect in vivo.