A transversal study was carried out to determine the frequency and the semiology of ankylosing spondylitis in outpatient rheumatology department at Lome (Togo). 13 of 2.626 examined patients in three years suffered of ankylosing spondylitis. All patients were male and a mean age of 23 at the appearance of the disease. Any had family case history but all presented a pelvis--rachis lesion. Three of them got a peripheral articular attack and 5 an enthesitis. Extra articular attack in 2 patients came out in the form of aqueous diarrhoea. Any patient had previous uveitis nor psoriasis, nor chronic enterocolopathy. All patients suffered from sacro-ileitis. Two patients got, in addition, some syndesmophytes. A bilateral coxitis made the disease more difficult to be treated in a patient whose ankylosing spondylitis was evoluting for 5 years. The symptomatology observed was comparable to the one in Southern Africa. It was like the one in Black Americans not carriers of HLA B27. Some further studies will make more precis the epidemiological and genetical profile of ankylosing spondylitis in Togo.