Background: To assess the impact of oral mucosa lesions on quality of life related to oral health (QLROH) and additionally to establish whether the etiopathogenicy of oral lesion is associated to the degree of QLROH impact. Material and Methods: In this cross-sectional study performed on a non-probability sample of 247 consecutively patients attending the oral medicine and pathology clinic the Spanish version of Oral Health Impact Profile-49 questionnaire (OHIP-49-mx) was applied. Responses were recorded on Likert-type scale whose values ranged from 0 (never) to 4 (always). Values greater than the 50 percentile (median) were considered as indicative of poor quality of life. All patients were orally examined and diagnosed. In accordance to their etiopathogenicy 6 study groups were formed: 4 corresponded to MIND classification for diseases (Metabolic, Inflammatory, Neoplastic, and Development groups), with ≥2 diseases and no-lesion group. To identify possible differences of OHIP-49 values between study groups an ANOVA (one factor) parametric and a chi square tests were performed (SPSS®20.0). Results: The OHIP-49-mx values were higher than the 50 percentile (established at 39) in metabolic, inflammatory, development, and ≥2 diseases groups, suggesting that this type of oral lesions negatively impact the quality of life. ≥2 diseasesgroup followed by metabolic and inflammatory diseases group (p 0.001) depicted worst quality of life. Functional limitation (p 0.003), pain, physical inability (p 0.001) and psychological disabilities dimensions exhibited greater values in all groups. Conclusions: Injured oral mucosa negatively impacts quality of life, specifically functional limitation, physical inability and psychological disabilities could lead to social isolation.To our knowledge, this is the first time that an association between QLROH and the etiopathogenicy of oral mucosal diseases is established.