Psoriasis impacts various aspects of patients' health-related quality of life and is associated with sleep problems. However, research discussing the associations between interleukin-17 blockage therapies and sleep problems in patients with psoriasis is insufficient. We aimed to assess the effectiveness of brodalumab in alleviating sleep problems in real-life patients with plaque psoriasis. This analysis was part of the single-arm, open-label, multicenter, prospective, cohort study, ProLOGUE (study period October 2017-March 2020), which involved Japanese patients with plaque psoriasis. Assessments included correlation of Medical Outcomes Study Sleep Scale-Revised (MOS Sleep-R) scores (Sleep Problems Index-II [SPI-II] and MOS Sleep-R subscale scores) with multiple patient-reported outcome scores and the Psoriasis Area and Severity Index (PASI) at baseline. Additionally, change from baseline in MOS Sleep-R scores was assessed at weeks 12 and 48 of brodalumab treatment. Seventy-three patients were enrolled (male 82.2%, median age 54.0 years). At baseline, the SPI-II score correlated with the Patient Health Questionnaire-8 score (Spearman correlation coefficient [ρ] = -0.474) and weakly correlated with the Itch Numeric Rating Scale (NRS; ρ = -0.366), Skin Pain NRS (ρ = -0.275), and all Treatment Satisfaction Questionnaire for Medication-9 domain scores (ρ = 0.270, ρ = 0.303, and ρ = 0.322 for effectiveness, convenience, and global satisfaction, respectively) but did not correlate with the PASI score. The SPI-II score and MOS Sleep-R subscale scores, except the Snoring score (p = 0.0319), did not significantly change from baseline to week 12 of brodalumab treatment. In conclusion, treatment with brodalumab did not improve overall sleep problems in real-life patients with plaque psoriasis, suggesting that sleep problems require attention in daily clinical practice (Japan Registry of Clinical Trials identifier, jRCTs031180037).