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 The multifactorial dimension reduction algorithm is considered as a powerful algorithm for identifying high-order interactions in high dimensional structures. In this study, information of 748 patients with Behcetchr('39')s disease who referred to the Rheumatology Research Center, Shariati Hospital, Tehran, and 776 healthy controls was used to identify the interaction effects between ERAP1 gene polymorphisms involved in the occurrence of Behcetchr('39')s disease using the multifactor dimensionality reduction algorithm. Data analysis was performed using MDR 3.0.2 software. The models obtained from the multifactorial dimensional reduction algorithm with balanced accuracy above 0.6 have been determined to increase the risk of Behcetchr('39')s disease. The multi-factor reduction algorithm has high power and speed in calculating the interaction effects of polymorphisms or genetic mutations and identifying important interactions.