Chlamydial abortion in small ruminants is a zoonotic disease mainly related to Chlamydia abortus. This bacterium is responsible for abortions and reproductive disorders in sheep and goats. Stillbirth and infertility, leading to important economic losses, are also associated to this pathology.In Algeria, abortion cases are frequently reported by veterinarians but, except for brucellosis, which is a notified disease in this country, abortive diseases are in general poorly studied. In order to detect the presence of Chlamydia antibodies in small ruminants in the region of Ksar El-Boukhari, 144 blood samples from 17 farms were collected. Sera were examined by indirect ELISA Kit (LSI VET Ruminant Serum Chlamydiosis, France). The test detects antibodies of the two most common Chlamydiaceae spp. affecting sheep and goats, namely Chlamydia abortus and Chlamydia pecorum. The assay was performed and results calculated according to the manufacturer's instructions.51 animals were positive, representing an observed prevalence rate of (35 ± 08) % and 15 herds were seropositive, representing an observed prevalence rate of (88 ± 15) %.The results suggest that the prevalence of Chlamydial infection is relatively large in small ruminants in this region. Veterinarians and people in charge of animal health should adopt an adequate policy of surveillance and prevention in order to control this pathology.