Purpose Psoriasis, affecting approximately 2% of the world’s population, often necessitates systemic treatments, with methotrexate (MTX) as a cornerstone therapy. Despite documented systemic side effects of MTX, concerns about its impact on male reproductive health persist. We aim to investigate low-dose MTX effect on hormonal, cellular and functional ability of male reproductive system. Materials and methods Our prospective study on 40 male psoriasis patients receiving low-dose MTX (<15mg/week) comprehensively investigates its effects on erectile function, sex hormones, and spermiogram parameters. Results After six months of MTX treatment, a significant decline in erectile function (p < 0.001) decreased total testosterone levels (p = 0.03) were observed. No significant reduction in sperm count was noted after six months of MTX treatment. Conclusions Our study highlights a significant decline in erectile function following low-dose MTX therapy, warranting further investigation into this potential side effect. While reassuring for sperm quantity and quality, the findings emphasise the necessity for larger cohorts and longer follow-up times to validate results and comprehend the complex interactions between MTX and male sexual health.