Introduction: Breast cancer cells and tumor stroma produce different cytokines and soluble factors. Cytokines, while playing crucial roles in immune responses to tumors, also favour tumor growth and progression. IL-7 and G-CSF are two cytokines that may exert influences on the pathophysiology of breast cancer. Materials and Methods: Sera were collected from 136 females with breast cancer before receiving chemotherapy or radiotherapy. The control group comprised of 60 healthy age-matched females without any acute or chronic diseases with no family history of breast cancer. Serum levels of IL-7 and G-CSF were measured by commercial enzyme linked immunosorbent assay. Results: While there was no significant difference in the level of G-CSF between patients ($92.81{pm}594.54$ pg/ml) and controls (0.00 pg/ml), G-CSF level in sera of patients with advanced stages of breast cancer was elevated compared to early stages (p=0.0001). Moreover, the highest level of G-CSF was seen in patients with N3 phase tumors (p=0.0001). IL-7 was slightly but not significantly higher in the control group ($0.04{pm}0.11$ pg/ml) in comparison with patients ($0.02{pm}0.10$ pg/ml). Interestingly, a significant increase in the level of IL-7 in patients with skin involvement was observed (p=0.001). Conclusion: Our results showed an elevation of G-CSF in sera of patients with advanced stages of tumor, while IL-7 elevation correlated with skin involvement of breast cancer. IL-7 can be produced by keratinocytes in skin tissue and may be involved in the pathologic establishment of metastatic tumor cells in skin.