The interior design industry in Taiwan is competitive and the survival rate is extremely low. This research applies the concepts of strategic group and positioning from the Porter theory to discuss the current competition situation of Taiwanese interior design industry; in addition, uses the Da Jin Chen Interior Design as an analysis case. The discussion applies strategic positioning, strategies, and the value chain to develop the foundations as a basis to inspect the industry. The empirical studies shows that by implementing appropriate strategic positioning, cost leadership, and differentiation methods in the field, the high correlations and conditions between strategic positioning, generic strategies, and value chain are essential strategic foundations for enterprises to cope with external competition.