The minor district (king amphoe) Na Muean was established on 9 October 1978 as a subordinate of Na Noi district, from which it was split off. Originally it consisted of the three tambons, Na Thanung, Bo Kaeo, and Mueang Li. It was upgraded to a full district on 4 July 1994.
Geography
The ferry over the Nan River Reservoir, created by the Sirikit Dam, connecting the village of Pak Nai in Na Muen District with the southern shore
The district is divided into four sub-districts (tambons), which are further subdivided into 48 villages (mubans). Bo Kaeo is the township (thesaban tambon) and covers the complete area of tambon Bo Kaeo. There are a further three tambon administrative organizations (TAO).