A survey of Taum Sauk Mountain State Park in Iron and Reynolds County, Missouri, was conducted from June 2011 to March 2012 to voucher the bryoflora. Several additional specimens previously collected in the park and deposited in the herbarium of the Missouri Botanical Garden (MO) were also re-examined. This checklist documents 123 taxa from within the park's boundaries (103 mosses, 18 hepatics and 2 hornworts), and includes 33 new county records including a confirmed Missouri station for Ulota hutchinsiae (Sm.) Hammar. Due to the park's large size and limited accessibility, this checklist, although preliminary, establishes a baseline for future surveys.