The Cimitarra Fault (Spanish: Falla de Cimitarra) is a sinistral oblique thrust fault in the departments of Antioquia, Bolívar and Santander in central Colombia. The fault has a total length of 136.5 kilometres (84.8 mi) and runs along an average northeast to southwest strike of 323 ± 3 in the Middle Magdalena Valley and Central Ranges of the Colombian Andes.

The fault is named after the Cimitarra River, Antioquia, a left tributary of the Magdalena River.

The Cimitarra Fault splays from the Palestina Fault in a northeasterly direction on the eastern border of the Central Ranges of the Colombian Andes, passes north of Barrancabermeja, and possibly connects to the Bucaramanga-Santa Marta Fault in the northeast. The fault displaces Jurassic to Cretaceous volcanic rocks, Mesozoic igneous rocks, a Tertiary erosion surface in the Central Ranges, and late Quaternary sediments. Portions of the fault are pre-Pliocene in age, since it is locally covered by undeformed Pliocene sediments. Farther northeast, the fault is overlain by young alluvial deposits of the Middle Magdalena Valley.

The fault is marked by well preserved fault scarps, long straight traces, displaced drainages, and it forms aligned river courses. The slip rate is calculated at 0.1 to 1 millimetre (0.0039 to 0.0394 in) per year.

• List of earthquakes in Colombia
• El Bagre Fault
• Honda Fault
• Ibagué Fault

• Paris, Gabriel; Machette, Michael N.; Dart, Richard L.; Haller, Kathleen M. (2000a), Map and Database of Quaternary Faults and Folds in Colombia and its Offshore Regions (PDF), USGS, pp. 1–66, retrieved 2017-09-18

• Gómez, J.; Montes, N.E.; Nivia, Á.; Diederix, H. (2015), Plancha 5-06 del Atlas Geológico de Colombia – 1:500,000, Servicio Geológico Colombiano, p. 1, retrieved 2017-06-06
• Paris, Gabriel; Machette, Michael N.; Dart, Richard L.; Haller, Kathleen M. (2000b), Map of Quaternary Faults and Folds of Colombia and Its Offshore Regions (PDF), USGS, p. 1, retrieved 2017-09-18

• Page, W.D (1986), Seismic geology and seismicity of Northwestern Colombia, San Francisco, California, Woodward-Clyde Consultants Report for ISA and Integral Ltda., Medellín, pp. 1–200