•Examines eight emotions of customer reviews in the restaurant context.•Introduces linguistic style matching to analyze readers’ diagnosticity of reviews.•Identifies six emotions and linguistic style matching significantly affect the perceived review helpfulness of customers.•Contributes to the evolving knowledge of customer perceived usefulness of online customer reviews. Many consumers feel overwhelmed by the unwieldy glut of information on peer-review websites (e.g., Yelp). Review helpfulness as a peer-rating mechanism on these websites enable consumers to quickly identify the most informative reviews and thus decreasing the information overload. The purpose of the study was to examine the influential factors on review helpfulness for restaurants on Yelp from affective content and communication style perspectives. The affective content was evaluated with eight emotional dimensions (joy, sadness, anger, fear, trust, disgust, anticipation, and surprise) in Plutchik’s emotion wheel. The communication style perspective was assessed with linguistic style matching (LSM). 262,205 pieces of consumer reviews were analyzed with negative binomial model. Both LSM and six out of the eight emotional dimensions (except anticipation and surprise) were found to have significant impact on review helpfulness. The study contributes to the knowledge body of review effectiveness from an innovative angle and provide pertinent managerial implications.