The aim of this work was to study ankylosing spondylitis (AS) prevalence and its clinical, radiological and genetic features in Ouagadougou. This was a cross-sectional study over two first years of rheumatologic practice (March 2006 to March 2008). All the patients having AS met the modified criteria of New York. HIV serology was negative. Thirteen cases of AS (0.9%) with 11 men were diagnosed among 1,439 rheumatologic patients. The average age of the patients at the beginning of the disease was 27.1 +/- 11.5 years. Bath Ankylosing Spondylitis Disease Activity Index and Bath Ankylosing Spondylitis Functional Index mean scores were, respectively, 47.8/100 and 44.46/100. No patient had presented extra-articular manifestations. Four (31%) patients had hip joint involvement. HLA B 27, among 11 patients, was positive in six (55%). Semiological features of AS among patients seen in Ouagadougou were similar to those of white race. HLA B27 prevalence in AS patients of Burkina Faso was similar to those of Afro-Americans.