Senior colonel is an army officer rank placed between a regular colonel and a major general. The rank typically exists in militaries that do not maintain a rank of brigadier general/brigadier.
In Nazi Germany, a rank equivalent to senior colonel, Oberführer, was used by both the SA and SS. In the branches of the Allgemeine SS (General SS) and Waffen-SS (Armed SS) the rank of Oberführer was widely used. The rank did not exist in the army (Heer), although the Kriegsmarine (navy) maintained the equivalent rank of Kommodore.
After World War II, armies in Asia, especially in the Communist sphere began establishing senior colonel ranks of their own. Today, the rank of senior colonel may be found in the militaries of China (Daxiao ( 大校)), North Korea (Taejwa (대좌)), Thailand ( Phan Ek Phiset (พันเอกพิเศษ)) and Vietnam ̣̣(Đại tá).
Most western militaries tend to equate a senior colonel as a "brigadier general in disguise"; however, this is not necessarily so. Nations which maintain senior colonel ranks may also have five general ranks (most such nations also having the rank of colonel general). A senior colonel is also not befitted honors of a general or flag officer. It is simply seen as the highest field officer rank before the general grades. In this sense, the rank may be seen as comparable to the rank of brigadier in the British and some other Commonwealth armies, similarly a senior field rank.