Psoriasis is a chronic relapsing dermatological disorder that significantly affects the patients' psychosocial well-being and quality of life (QOL). This study aimed to determine the proportion of severely impaired QOL, the factors associated with severely impaired QOL, and its correlation with depression among semi-urban populations on the Northeast Coast of the Peninsular Malaysia. A cross-sectional study was conducted among 257 patients with psoriasis at the Dermatology Clinic of Hospital Sultanah Bahiyah via a self-administered questionnaire that included sociodemographic profiles, the validated Malay version of the Dermatology Life Quality Index (DLQI), and the Malay version of the Beck depression scale. The data were analysed using logistic and linear regression models. About 20.5% of the patients had severely impaired QOL quality of life, while 79.5% of the patients had non-impaired QOL. Multiple logistic regression analysis showed that the psoriatic severity [Adjusted OR = 1.91, 95% CI: 1.76, 9.93; < 0.001] and exposed area [Adjusted OR 2.93, 95% CI: 0.38, 2.29; = 0.050] had a significant association with severely impaired QOL. Among the patients, 18.7% had a positive result in the screening for depression, which revealed a significant association between QOL and depression scores [r = 0.47, 95% CI: 0.35, 0.56, < 0.001]. Psoriasis can impair QOL and have a relation with mental health. Regular screening for depression among patients with psoriasis is a beneficial strategy for the early detection of depression, especially in semi-urban areas.