Psoriasis is a chronic disease centered on tumor necrosis factor (TNF), interleukin (IL)-23, and IL-17 axis. While psoriasis patients benefit from biologics targeting TNF, IL-17s, and IL-23 nowadays, suppression of these molecules could modulate the balances of immune systems. However, the incidence of autoimmune disease and T-helper 2 reaction during biologic treatments for psoriasis patients is not well documented. We retrospectively examined antinuclear antibody (ANA), eosinophil counts, and immunoglobulin E (IgE) levels for psoriasis patients who underwent biologic treatments in our dermatology clinic from June 10, 2010 to January 29, 2020. A cumulative total of 199 biologic treatments were performed for a total of 128 psoriasis patients. Compared to the non-biologic group of 109 psoriasis patients who received non-biologic treatment, patients treated with infliximab showed more incidents of high ANA (14%, p = 0.039) and high eosinophils (14%, p = 0.021). The use of brodalumab increased incidents of high eosinophils (21%, p = 0.005) but did not affect increase in ANA and IgE. The increase in high IgE level was observed significantly more during the use of risankizumab (15%, p = 0.011). Methotrexate was the most frequently used concomitant systemic treatment, but methotrexate did not affect ANA, eosinophil counts, and IgE levels. Since the biologics for psoriasis treatment modulate the balance of T-helper cells, careful observation is required to detect unexpected changes of systemic immune conditions under biologic treatments.