Product design affects many aspects of people¡¦s life. This research use qualitative and quantitative methods, and focus on how simple design cause different consumer responses. First of all, we process a content analysis aiming for household and digital product, and then we conduct the definition and characteristics of simple design. Second, we use experimental design to figure out the pattern of consumer responses to product design both psychological and physical. For psychological responses, we observe the consumer expectation and satisfaction in product appearance, assortment size and functional information; we also exam the different decision making tendency (Maximizer & Satisficer) in consumer approach behavior. According to our research, we conclude that the required elements of simple design are (1) Single Color, (2) Unique Personality, (3) Simple Shapes, (4) Practical Function, (5) Easy to Use, (6) Match, (7) Materials, (8) Aesthetics and (9) Culture & Emotion. For product external appearance, there is high expectation for simple design, and also satisfaction still has a big room to improve. To be more specific, in the aspects of attention drawing, unique symbol and ergonomic is the biggest gap between expectation and satisfaction. In the part of assortment size, simple design causes a higher expectation when the size is large. However, satisfaction did not drop as previous studies suggested, it remains indifferent which could be the suggestion for future product development. In function information, it plays a important role in digital product which means mainly simple designed appearance can only achieve limited benefits. In behavioral response, satisfaction and approach behavior have positive relation, and the responses of store are apparently stronger than the responses of single product. In different decision making tendency, product personality, attention drawing and assortment size are significant, but there is no clear result for function information.