Background: Sexually Transmitted Infections (STIs) are among the most important causes of maternal and neonatal morbidity and mortality. It remains a significant public health problem and disproportionately affects women posing a large public health burden in low and middle-income countries. However, there is little information on the magnitude of self-reported syndromes of STIs among reproductive-age women in Ethiopia. Aim: This study aimed to determine the magnitude of self-reported syndromes of sexual transmitted infections and its associated factors among women of reproductive age in Ethiopia. Methods: The study was based on the data from the Ethiopian Demographic Health Survey of 2016. The data on the status of self-reported STIs were extracted from the individual women dataset, and a total of 15,683 reproductive-age women were involved in the study. Since the data has a hierarchical and cluster nature sampling weight was applied for all analysis procedures to account for complex survey design. Rao-scot chi-square test that adjusts for complex sample design was used to examine the association of outcome and independent variables. In, multivariable analysis, the level of statistical significance was declared at P-value ≤ 0.05. Findings and conclusions: The magnitude of self-reported STIs was 3.0 % (95% CI: 2.92–3.08). Among self-reported syndromes of STIs only, 33.3 % (158) seek care for sexually transmitted infections. Age (Adjusted Odds Ratio (AOR = 2.15; 95%CI:1.4, 3.4)), marital status (AOR = 1.72; 95%CI:1.02, 2.90), women attending higher education and above (AOR = 2.67; 95%CI:1.57,4.57), history of termination of pregnancy (AOR = 2.85; 95%CI:2.0,4.08), and risky sexual behavior (AOR = 1.72; 95%CI:1.02,2.90) were found to be associated with self-reported syndrome of sexually transmitted infections. The magnitude of self-reported syndromes of STI and health care seeking behaviors among reproductive-age women was found low. Therefore, the government should enhance the awareness of women for sexually transmitted syndromes, and increase accessibility of STI services. Moreover, qualitative studies should be done to identify the demand, supply, and barriers related to STI among women of reproductive age women in Ethiopia.