Nowadays developing industrial clusters has been emerged as an important regional development approach and turned attentions of many researchers and propels governments to develop and implement cluster development programs. The programs have been designed in order to upgrade performance of clusters. Experts of the field believe in complexity and multi-dimensionality of performance concept in industrial clusters which summon more researches to clarify the concept and increase efficiency of cluster development programs. This research identified performance determinants of Iranian industrial clusters and investigated their priority which resulted in grouping of clusters. The research conducted with systematic review of the literature and interviews to develop list of determinants and with online participation of 22 cluster development agents (CDAs). Determinants have been reorganized into Q-sort by CDAs which clarified five groups of participants with deferent priority of determinants. The study can lead policy makers to find the key components affecting performance in clusters and therefore increase efficiency of policies.