Microwave-assisted foam-mat drying was carried out to produce Centella asiatica powder. Firstly, the effect of foaming agent (egg albumin) and stabilizer (carboxymethyl cellulose) concentration on the stability of Centella asiatica foam was studied. Secondly, the change of color of Centella asiatica powder at different foam layer thickness and microwave power was investigated. The results indicated that the foam mixture reached the most stable state when the ratio of foaming agent and foam stabilizer was within a specific range of values, here 15% egg albumin and 1.4% CMC (relative to the sample weight); The optimal powder color was obtained at a foam thickness of 4 mm and a microwave power of 130 W. The results of this study were a stepping-stone for optimizing the parameters in the process of producing Centella asiatica powder by using microwave-assisted foam-mat drying method.