Background: Interleukin 23 (IL 23) and Interleukin 17 (IL 17) are two vital cytokines encountered in cutaneous and non-cutaneous immune-mediated inflammatory conditions and also share in cancer development. Basal cell carcinoma (BCC) is a well-known skin tumor with a high incidence and locally invasive effect but rare metastatic potential and a low mortality rate. Aim: To investigate the association of IL 23 and IL 17 in BCC by immunohistochemical evaluation of both. Methods: Based on a study conducted by us, twenty patients with BCC previously treated with intralesional methotrexate were involved in this study. Both interleukins were evaluated in tumor cells and inflammatory cells pre and post treatment, and expression was compared with treatment response. Results: Overexpression of IL 23 and IL 17 was observed in BCC, moreover, both were decreased post treatment with a significant difference (p