Introduction: Krüppel-like factor 4 (KLF4) is a transcription factor of anti-inflammatory and anti-thrombotic properties not studied in psoriasis yet. Aim: To analyze the clinical value of the serum KLF4 level in psoriatics and elucidate the interplay between disease activity, metabolic or inflammatory parameters and systemic therapy. Material and methods: The study enrolled thirty-four psoriatics and fifteen healthy subjects. Blood samples were collected before and after twelve weeks of treatment with methotrexate or acitretin. Serum KLF4 levels were measured using immune-enzymatic method. Results: Serum KLF4 levels in psoriatic patients did not statistically differ comparing to the controls (p > 0.05). However, in severe psoriasis, KLF4 was significantly higher than in healthy ones before treatment and normalized after treatment to baseline levels of controls (p < 0.05, p > 0.05, respectively). KLF4 positively correlated with body mass index (p = 0.038) but not with psoriasis severity, nor inflammatory or metabolic markers. Interestingly, many pro-atherogenic parameters were shown as variables independently predicting the levels of KLF4. No significant effect of three-month systemic treatment on KLF4 was found. Conclusions: KLF4 may be a novel independent indicator of the proatherogenic risk in psoriatics, especially with a severe form or obesity.