The name "Kynšperk" (literally meaning "Kingsburg") has been associated with the town since 1232 when the monastery in Doksy received a permission from King Václav I (also denoted as Wenceslaus I of Bohemia) to found a town bearing this name. The original location of the town, however, was not within its present-day borders but approximately 2 kilometres to the east at the confluence of the Malá and Velká Libava Creeks. The later site of the town of Kynšperk spreading around the castle bearing the same name, i.e. on the present-day territory of Kynšperk nad Ohří is documented later, during the reign of Charles IV.
The origin of the first inhabitants cannot be precisely determined, nonetheless, medieval population had already been quite diverse as evidenced by historical monuments. The source of livelihood of the local people was changing in the course of time, whereas original agriculture and minor handicrafts were complemented with joinery, which experienced a major boom from the 18th century, and subsequently also with mining. Additional fields of industry appear in the 19th and 20th century, e.g. metalworking, textile industry, etc.
One of the most renowned natives is born in Kynšperk in the second half of the 19th century (1871), i.e. Kašpar Herrmann, the inventor of offset printing. The town's population changed quite significantly after World War II. As elsewhere in the border regions, a part of the German inhabitants was replaced by Czechs and Slovaks – newcomers from inland, returnees from the Czech and Slovak communities in the neighbouring countries, as well as Poles, Hungarians, Serbians, and other nations.
The original development was partly replaced in the 1950’s when new apartment houses were built in the vicinity of Zámecký vrch (Castle Hill) on the site of original ones. The town began spreading southwards in the 1960’s with the building of a new housing estate. Unlike other towns, though, Kynšperk has retained its original articulated town layout, making it an ideal place for walks through its picturesque streets and offering a marvellous view from above. The livelihood of the population changed with intense building development, many men found jobs at the Tisová power station or the mines in Sokolov, and women in the textile factory in the village of Libavské Údolí.
In Kynšperk, people continue to make furniture, both metal and wooden, they repair agricultural and forest machinery, or they engage in agriculture in nearby villages of Chotíkov and Zlatá, as well as in transportation, municipal utilities, retail, or the budget sphere.