Accessibility means that any product, service, technology or application can be understood and used by everyone, including the disabled and the elderly. In web applications, this concept means that the entire target audience can access the application, use the application, and understand the content. There is international web accessibility standard that guide the developers by defining the necessary controls to develop accessible applications. In this study, 110 papers related to web accessibility evaluation and metrics published between 2008 and 2018 were examined by systematic mapping and the findings were reported. The results revealed that the number of published papers were increased since 2008, automatic accessibility evaluation methods were the most common method applied in the studies, generally e- government web sites were evaluated and WAB is also used as web accessibility metric.