The sign languages of the Deaf are visual natural languages that are created among the Deaf and transmitted from generation to generation within their community. Although research on sign languages and Deaf cultures is indispensable for understanding human languages and cultures in general, few studies have examined the sign languages of Africa, and there are no general introductions to the subject. Therefore, this paper outlines the sign languages of Africa and points out future research issues. It presents an original sign language map of Africa, and reviews the following, based on analyses of data collected through fieldwork and documentation.(1) Africa has at least 23 sign languages. Most are named after African nations and not after African ethnic groups. Of the 23 sign languages, some originated in Africa and others from foreign sign languages. In addition to these 23 sign languages, the Deaf on the African continent use other sign languages, including “Franco-American Sign Language” observed in Cameroon, which is a pidginized American Sign Language that is shared among Deaf communities in several nations in West and Central Africa. Some of the African sign languages have distributions that are completely independent of those of African spoken languages.(2) Foreign sign languages have been introduced to Africa, mainly from Europe and America. At least 13 foreign sign languages have been introduced to at least 27 African nations. Most of these introductions were related to the spread of Deaf education in the postcolonial era and not to colonial rule by Western powers. The presence of sign languages from America and Nordic countries is significant in Africa, and these languages have common characteristics, as they are from countries that are advanced in the field of Deaf education using sign languages.(3) In the urban Deaf community of Cameroon, multi-ethnic Deaf people share a unique sign language. The ethnic diversity of Cameroon divides neither the sign language of the Deaf nor their Deaf identity.On the basis of these results, I advocate a model of a “national Deaf community”, which can be stated as follows: “a national Deaf community has been newly constructed in each nation despite the linguistic and ethnic diversity of Africa.” As a conclusion, I suggest future research that is needed to understand “other linguistic cultures of Africa” considering the autonomous dynamics of sign languages.