Background. Acute appendicitis (AA) is a common condition in general surgery, often with serious consequences such as septicemia and intra-abdominal infection. Mean platelet volume (MPV) - a platelet parameter - could be an index of inflammation. We carried out the present study to perform a meta-analysis of AA and MPV. Methods. A systematic search was conducted in databases of PubMed and Embase from 1966 to 2015. Weighted mean difference and 95% confidence interval (CI) were then calculated. Finally, statistical analysis was carried out using Stata 12.0 software. Results. Of the 88 selected studies, five case-control studies met the selection criteria. These cases, comprised1416 cases of AA and 685 controls. The results showed a prominent decrease of MPV levels in patients suffering from AA, compared to the control group. (weighted mean difference, -0.64; 95% CI, -0.74 to -0.54; P=0.037). Conclusions. AA cases had a lower MPV than the controls, which supports MPV as a potential biomarker of AA.