OBJECTIVES: To validate and compare the psychometric properties of two generic preference-based HRQoL instruments, EuroQol (EQ-5D) and Short-Form 6D (SF-6D) among psoriasis patients in China. METHODS: Validity of the EQ-5D and SF-6D was examined with the patients in conjunction with Dermatology Life Quality Index (DLQI). Responsiveness was tested using the effect size (ES), relative efficiency (RE) and receiver operating characteristic (ROC) curves. Agreement between EQ-5D and SF-6D was tested using intra-class correlation coefficient (ICC) and Bland-Altman plot. RESULTS: A total of 150 moderate to severe patients were included with 50% female, mean age of 43.87 and mean disease duration of 5.19 years. The mean utility scores (SD) were 0.64 (0.32) for EQ-5D and 0.72(0.12) for SF-6D. There were no serious floor effects for EQ-5D and SF-6D but large ceiling effects for EQ-5D existed. Validity was demonstrated by the moderate to strong correlation coefficients (range: 0.50-0.71, P<0.001) for six of the ten hypotheses in both instruments. Both of EQ-5D and SF-6D showed a well discriminative capacity similarly (ES=0.98-1.27, ES= 0.99-1.26) between groups with different psoriasis specific health status. RE showed that SF-6D (6.00-39.00%) was more efficient than EQ-5D in three domains of DLQI ( recreation, relationships and treatment). Conversely, SF-6D (ￚ1.00 - ￚ13.00%) was less efficient than EQ-5D in three domains of DLQI ( symptoms and feelings, daily activities and work and studies). The areas under ROC of them all exceeded 0.5 (0.71- 0.84, P<0.001). Poor agreement between them was observed with ICC (0.38, P<0.001) and Bland-Altman plot analysis. CONCLUSIONS: This study provides evidence that EQ-5D and SF-6D are valid and sensitive preference-based HRQoL instruments in Chinese patients with moderate to severe psoriasis. SF-6D may be a more effective tool with lower ceiling effect. Further study is needed to compare other properties, such as reliability and longitudinal response.