The paper aims to design a new type of water filter tray structure for capsule dairy product package to increase the richness of milk foam in capsule dairy products and solve the problem of insufficient foaming of existing capsule dairy products. The capsule structure was designed with Autodesk Inventor and a 3D printer was used to make the model. The foamability and foam stability were used as evaluation indicators. The effect of the water filter tray structure on the foam quality of the capsule dairy products was verified by experiments. Among all water filter tray structures, the “3 split groove layers”-“cylindrical guide column”-“round holes” water filter tray had the best effect on the richness of the foam. This new water filter tray structure of capsule dairy product package could apparently improve the foaming characteristic of dairy products. The foamability was up to 88%, which was 38% higher than the original capsule; and the foam stability was 80%, which was 12% lower than the original capsule. The new water filter tray structure for capsule dairy product package can obviously increase the foam richness of capsule dairy products, and by using the capsule coffee machine, we can make rich milk foam.