Prioritization of competitive suppliers can be considerably challenging in the absence of predetermined and systematical assessment procedures. This study develops an integrated methodology of quality function deployment (QFD) and complex proportional assessment (COPRAS) methods under fuzzy environment to prioritize competitive suppliers. In the proposed model, QFD is utilized to determine the evaluation criteria weights by considering the customers' views and COPRAS is used to generate the ranking orders of the competitive firms. The proposed approach allows to capture the uncertainty and vagueness of decision makers' judgements with the aid of interval-valued Pythagorean fuzzy (IVPF) sets. An aircraft manufacturer is used as an example for illustrating the proposed model and the obtained results are compared with IVPF WASPAS method.