Background Gastroesophageal reflux disease (GERD) is very common. Salivary pepsin detection has previously been considered as a method for GERD diagnosis. We performed a meta-analysis to investigate the utility of salivary pepsin assay as a diagnostic tool of GERD. Material/Methods PubMed, Web of Science, the Cochran Library, and EMBASE (from January 1980 to 23 October 2018) were searched for pepsin in saliva for GERD diagnosis. We summarized the retrieved specificity, sensitivity, negative likelihood ratio (NLR), positive likelihood ratio (PLR), diagnostic odds ratio (DOR), and receiver operating characteristic (ROC) curves data in the meta-analysis. Results In final analysis, a total of 5 studies were included. The summary sensitivity, specificity, NLR, and PLR were 0.60 (95% CI 0.41–0.76), 0.71 (95% CI 0.51–0.86), 0.56 (95% CI 0.34–0.93), and 2.1 (95% CI 1.1–4.1), respectively. The pooled DOR was 4 (95% CI 1.0–11.0) and area under the ROC was 0.70 (95% CI 0.66–0.74). Conclusions The meta-analysis showed that pepsin in saliva has moderate diagnostic value for GERD, and is not as helpful as previously thought.