Abstract: Objective To investigate the effect of psoriasis on health-related quality of life (HRQOL) and the relationship between psoriasis severity and quality of life. Methods Clinical data about 124 psoriasis patients (53 with active psoriasis and 71 with stable psoriasis) in out-patient department in our hospital from February 2013 to March 2014 were retrospectively analyzed. The psoriasis area and severity index (PASI) score of patients were recorded and measured, and all patients had completed the following HRQOL questionnaires: the dermatology life quality index (DLQI) and generic 36-item short-form (SF-36). Results The mean score of PASI, DLQI questionnaire and SF-36 were 11.6±6.1, 7.4±5.8 and 53.8±15.0, respectively. The mean PASI score and DLQI score in patients with active psoriasis were signifcantly higher than in patients with stable psoriasis (P< 0.01), and the mean SF-36 score in patients with active psoriasis was signifcantly lower than in patients with stable psoriasis (P< 0.01), which suggested that the HRQOL of patients with active psoriasis were much lower than that of patients with stable psoriasis. A signifcantly positive correlation was found between PASI score and DLQI score (r=0.645, P=0.000). While, a negative correlation between SF-36 score and PASI score was observed (r=-0.209, P=0.020). There was no signifcant correlation between DLQI score and SF-36 score (r= -0.114, P=0.208). Conclusion Psoriasis can lower the level of HRQOL of patients. The effect of psoriasis on HRQOL is higher in patients with active disease and there is signifcant correlation between HRQOL and psoriasis severity.