In the context of ethnic dining services, authenticity is the key ingredient. This study aims to investigate the impact of servicescape dimensions on consumers’ prepurchase authenticity perceptions and patronage intentions to ethnic restaurants. The authors propose that three key dimensions of the servicescape—the physical setting, service providers, and other customers—provide ethnic-associated cues for consumers to assess authenticity in the preconsumption stage. Empirical results from a between-subject experimental design suggest that servicescape dimensions can induce preconsumption authenticity perceptions of ethnic restaurants and that the dimensional cues interplay to affect authenticity assessments. Furthermore, a customer’s ethnicity (referent ethnic vs. mainstream) affects how she/he interprets servicescape cues and, therefore, his/her authenticity assessment. The perceived authenticity, together with a consumer’s trait of cosmopolitanism and his/her familiarity with such ethnic restaurants, consequently affect consumers’ patronage intentions. These findings contribute to hospitality research on consumers’ authenticity assessments of ethnic restaurants. Furthermore, managerial implications for ethnic restaurants in terms of marketing strategies will be discussed.