Background: Syphilis is a disease caused by bacteria called Treponema pallidum. It is transmitted through sexual contact, blood transfusion and via vertically from mother to fetus in utero. Untreated syphilis during pregnancy can greatly affect pregnancy outcome, resulting in spontaneous abortion, and stillbirth.The aim of the study was to determine the sero-prevalence of syphilis among pregnant women attending for Antenatal Care (ANC) service.

Methods: A cross-sectional study was conducted from January to June, 2016 at Jimma University specialized hospital, Southwest Ethiopia. A total 181 study subject were recruited by conveniently. Socio demographic and clinical data was collected by pre-tested structured questioners. Two milliliter of blood was collected to determined sero-prevalence of syphilis using Florescent Treponema antibody Absorption (FTA-Abs) test. The data was analyzed by using SPSS version 21. The association between independent and dependent variables was determined. P-value less than 0.05 was considered as statistically significant value.

Result: Among a total of 181 participants, only 2/181 (1.1%) women were seropositive for syphilis. Among participants, 41.4% of them were found in age group of 21-25 years, 77.9% of them were married while 3.9% were widowed. 66.3% of them were from urban area. Residence and sexual status of syphilis showed significant association.

Conclusion: Syphilis seropositive cases were observed among married women who come from rural area with age group of 26-35 years. Therefore, health education on etiology, prevention and control of syphilis has to be provided for the community.