The Republic of Sierra Leone Armed Forces are the armed forces of Sierra Leone, responsible for the territorial security of Sierra Leone's borders and defending the national interests of Sierra Leone, within the framework of the 1991 Sierra Leone Constitution and International laws. The armed forces were formed after independence in 1961, on the basis of elements of the former British Royal West African Frontier Force, then present in the Sierra Leone Colony and Protectorate.

Sierra Leone, officially the Republic of Sierra Leone, is a country on the southwest coast of West Africa. It shares its southeastern border with Liberia and is bordered by Guinea to the north. With a land area of 71,740 km2 (27,699 sq mi), Sierra Leone has a tropical climate and with a variety of environments ranging from savannas to rainforests. According to the 2015 census, Sierra Leone has a population of 7,092,113, with Freetown serving as both the capital and largest city. The country is divided into five administrative regions, which are further subdivided into 16 districts.