Abstract/Summary: In rural areas of the United States, an estimated ~1.8 million people lack reliable access to safe drinking water. Considering the relative dearth of information on water contamination and health outcomes in Appalachia, we conducted a systematic review of primary data studies published from 2000-2019. Of the 3,452 records identified for screening, 85 met our eligibility criteria. Most studies were conducted in Northern (32%, n=27) and North Central (24%, n=20) Appalachia, and only 6% (n=5) in Central Appalachia. Across studies, E. coli were detected in 10.6% of samples. 32% (n=27) of studies assessed health outcomes, but only 4.7% (n=4) used case-control or cohort designs (all others were cross-sectional). The most commonly reported outcomes were detection of PFAS in blood serum (n=13), gastrointestinal illness (n=5), and cardiovascular-related outcomes (n=4). Overall, based on the number and quality of eligible studies identified, we could not reach clear conclusions about the state of water quality, or its impacts on health, in any of Appalachia’s subregions. More epidemiologic research is needed to understand contaminated water sources, exposures, and potentially associated health outcomes in Appalachia.