New product development is a modern approach to deal with the environmental changes and an introduction to enter the competitive atmosphere is a challenging condition. By realizing the critical aspects of success of the new product and selecting a compatible model of variables in these aspects, companies may create a unique context for developing the product; but whether in terms of the multiplicity of the decision-making choices or the inherent conflicts of the response atmosphere’s variables, the complexities of the current world have caused disruption and inefficiency in the field of optimal selection and decision making. The aim of this study is to identify the critical aspects of development of the new product in the Sedan automobile class and to offer a morphological model of that by investigating the ideas and comments of the experts and scholars. In this regard, by using the Importance-Performance Analysis (IPA) method, the proposed method assesses the mode of the organization; and with the General Morphological Analysis, it assesses and searches for the most compatible decision-making variables to find the fully optimal and compatible solutions. After studying the subject literature, seven critical aspects are selected for the product development and three purposes are chosen for limiting the morphological model. Finally, four fully compatible configurations and one configuration are proposed with the entrance of the aspects determined from the output of IPA method. The innovative solution in solving the morphological model and its integration with IPA method are considered as the innovations of this study.