A field survey of commonly used medicinal plants in the district of Paksan, Bolikhamsai Province in the Lao People's Democratic Republic (Lao P.D.R.) indicates that 55 species of plants, belonging to 49 genera in 31 families of vascular plants, are used in day-to-day medical therapy. Lao names along with uses and preparations for remedies are given. Seven species have medicinal uses that overlap with uses reported in the literature. No medicinal uses have been previously reported for 31 of the species collected based on ethnobotanical field interviews, signifying that their uses may be unique to Laos. Nine of the 31 previously unreported species are mentioned as medicinals multiple times, indicating that further research may be warranted.