Mukdahan (also Mukdaharn) is one of the north-eastern provinces (changwat) of Thailand. Neighboring provinces are (from south clockwise) Amnat Charoen, Yasothon, Roi Et, Kalasin, Sakon Nakhon and Nakhon Phanom. To the east it borders the Mekong River, across which lies Savannakhet Province of Laos.