Abstract: The primary and spatial structures of coffee- bean α- galactosidase were studied to further determine its structure and function. The results showed that the enzyme protein was hydrophilic,acidic and stable. The secondary structure was dominated by α- helices and random coils. The three- dimensional structures of coffeebean α- galactosidase were constructed based on the template of rice α- galactosidase by homology modeling because their spatial structures were similarity.The side of the structure model was 8 α- helices and 8 β- turns,and the other was 8 β- turns. The experimental results provided the theoretical basis for the study on the spatial structure and catalytic site of coffee- bean α- galactosidase.