Background: Remote monitoring was used to assess and manage skin diseases. Objective: To investigate to what extent smartphone photographs along with a self-reported body region (BR) score can be used to evaluate psoriasis severity. Methods: Psoriasis severity was assessed in the clinic using the psoriasis area and severity index and the physician's global assessment. On the same day, the patients took a photograph of a representative lesion from 4 BR (head/neck, upper limbs, trunk, and lower limbs) and completed a questionnaire about BR score. The photographs were rated by 5 dermatologists. Intraclass correlation coefficients with 95% CIs were calculated. Results: Overall, 32 were included, of which 6% had almost clear, 69% had mild, and 25% had moderate psoriasis. Perfect agreement between the self-reported and the doctors’ BR score was observed for 59%, and near-perfect agreement (deviation of maximum 1 score) was 92%. The intraclass correlation coefficient between clinical and photographic psoriasis area and severity index was 0.78 (95% CI, 0.55-0.90), and for physician's global assessment, perfect agreement was 53%. Conclusions: The agreement between psoriasis severity assessed clinically and by photographs was good in a study setting. This gives the opportunity to remotely assess psoriasis severity by combining photographs with self-reported BR scores.