The purpose of this work is to appear the design evaluation and decision in each phase of design process based on the design concept led by a commodity concept. In the first half of this paper, through considering both the definition of these concepts and process of cognition and evaluation, decision, the model how the design concept would lead to the concrete design was examined and made hypothetically. Some problems and consideration of the design evaluation and decision in the design process were shown in the latter half.It is found that standard evaluation by use of design check list table which has crisp evaluation is creative process and makes more significant role than we have ever thought in the process flow of the design evaluation.