This study applies content analysis to investigate online and published restaurant reviews of full-service restaurants in Auckland. By interpreting the underlying meanings and identifying key words of each review, the evaluation criteria adopted by two kinds of reviewers are revealed. The findings of this study show that, while the quality of food and service are always the primary measures for online and professional restaurant reviewers, there are several differences between these two types of reviews. Cost draws attention from both online and professional reviewers, but only online reviews involve strong personal judgments about price fairness. As for themes that only appear in one type of review, only online reviewers talk about their dining companions, while only professional reviewers provide specialised information that is not accessible to the public about the chef, owner and operational circumstances of the restaurant. The criteria adopted by online and professional reviewers are compared and the differences explored from the perspective of the association between social differentiation and reviewers’ and audiences’ writing and reading habits. Furthermore, this study makes recommendations for restaurant practitioners about maintaining their restaurants’ online reputation, and enriches the literature that employs user-generated content as a new data source.