The growing size of the aging population is becoming a significant issue for many countries, and the United Nation has proposed “aging-in-place” as a solution, which can be implemented with the help from ambient, assisted living system. Many previous works have focused on the emergency and autonomy services, and lack studies on comfort service. The purpose of this study is to conduct an empirical study of using multimodal interfaces in ambient assisted comfort services for senior citizens targeting participants at their home, with a prototype system that supports both traditional and multimodal interaction methods. Scenarios have been defined that include common tasks such as item finding, communication, media access, and setting calendar events. 15 senior citizens have answered questionnaires and scale rating questions from each performed scenario. The comparison between traditional and multimodal interface was made through a set of evaluation criteria including efficiency (time), pleasantness, fatigue, naturalness, ease of learning, and perceived effectiveness. The results showed that all the participants have enjoyed the multimodal interface, and showed better efficiency than traditional interaction method.