This paper describes a Voice User Interface(VUI) method and a design guideline tool which supports the studies for domestic appliance. This issue covers specification of user requirement and selection of appropriate VUI to represent speech generation. The criteria for paper is interaction design to enhance user engagement. The studies were carried out to measure prototype of domestic appliance such as a refrigerator, a washing machine, a Gimchi refrigerator, an oven range, a dishwasher and an air conditioner. This paper is presented a study of user preferences and suitability. The results of these findings to voice interface design are discussed and it is suggested that VUI guideline and optimal prototyping can provide a useful application tools in the design process.