Senior captain is a rare military rank which is used in some countries armed forces, navies and merchant marines.
In some armies of the world, the senior captain is a rank between a regular captain and a major. The rank is often only found in armies and air forces. A similar position to that of senior captain is the rank of senior colonel.
The rank of taewi (대위) in the military of North Korea and the rank of da wei (大尉) used by the People's Liberation Army between 1955 and 1965, are often translated as senior captain. However, the ranks and insignia derive from the practice of the Soviet Army, which has, like the Red Army before it and the Russian Army today, four company-grade officer ranks, one captain rank and three lieutenant ranks. The literal translation of those four ranks in Chinese and Korean are junior(-grade) officer, mid(-grade) officer, upper(-grade) officer, and senior(-grade) officer. Since the PLA today uses only three-company grade officer ranks, it has become conventional to translate shang wei (上尉) which originally corresponded to the Soviet rank of senior lieutenant, as captain, and hence da wei, which corresponded to the Soviet rank of captain, as senior captain. The corresponding fourth junior office rank of the Vietnamese Army, đại úy, is usually translated as captain.
In the Afghan National Army and the Afghan National Police, between the ranks of turan (captain) and Jagran (major) is the rank of jag turan. In the case of the Afghan National Police, the rank of jag turan is most commonly translated as "staff captain".
The rank of senior captain is rare in Western militaries, but can be found in the German military, where the rank of Stabshauptmann (Stabskapitänleutnant in the Navy) was created in 1993 for officers of the Militärfachlicher Dienst (former NCOs in specialist positions) who could not be promoted to field grade. The Belgian Armed Forces use the rank of captain-commandant as a standard rank. Italy uses a title of primo capitano for captains (army) that have held the rank of captain for a long time, currently nine years or longer.