OBJECTIVES: The OSSAS and OSIS are patient reported outcome measures developed using focus groups to assess facial Oily Skin (OS) severity and the psychosocial impact of oily skin, respectively. This study examines the validity and reliability of these measures in a cross-sectional study. METHODS: The OSSAS, OSIS and concurrent measures (Skindex and AcneQoL) were administered to 202 OS patients at seven sites across the USA. A sub-group of 152 patients returned 1-2 weeks later for test-retest reliability evaluation. RESULTS: Of the 202 participants, 72.8% were female; 64.4% had acne in addition to OS. Item reduction analyses resulted in a 14 item OSSAS with 'Sensations' (5 items), 'Tactile' (3 items) and 'Visual' (4 items) domains, a single blotting item, and a single overall oiliness item. The 6 item OSIS includes Annoyance (3 items) and Self-Concept (3 items) domains. Confirmatory factor analysis provided support for the construct validity of the final item-scale structures. The OSSAS and OSIS scales had acceptable item convergent validity (item-scale correlations >0.40) and floor and ceiling effects (<20%). Cronbach's alpha coefficients ranged from 0.83-0.89 for the OSSAS and 0.82-0.87 for the OSIS, demonstrating excellent internal consistency. The a priori criterion for test-retest reliability (ICC=0.7) was met for one of the three OSSAS domains and one of the two OSIS domains. Correlations of the Skindex-29 and Acne-QoL scales with the OSSAS (range: -0.08-0.38) and OSIS (range: 0.37-0.73) domain scores met content expectations for these scales. OSSAS and OSIS domains distinguished among groups of patients who differed in terms of both patient reported facial OS severity (p<0.0001) and patient reported bother associated with OS (p<0.0001). CONCLUSION: The OSSAS and OSIS provide valid self-report measures of facial OS severity and the emotional impact of OS, respectively. Test-retest reliability and responsiveness of these measures require further evaluation.