Introduction Patients with elevated anti-streptolysin O (ASO) titers (ASOT) and recurrent tonsillitis episodes are known to be at higher risk for rheumatic heart disease (RHD). However, there is no data regarding prevalence of RHD in this high risk population. In this study, we aimed to screen ambulatory patients with elevated ASOT and recurrent tonsillitis episodes using echocardiography for identification of RHD. We hypothesized that prevalence of RHD is higher in this patient group compared to general population. Methods 102 patients (10.33 ± 4.01 years, 50.98% female) who were diagnosed with recurrent tonsillitis and had elevated ASOT were included this study. Echocardiographic evaluation was performed by an experienced cardiologist. Results Echocardiographic examination revealed definite RHD in 2/102 (1.96%) patients and borderline RHD in 3/102 (2.94%) patients. Conclusion Our study demonstrates a high prevalence of RHD in patients with recurrent tonsillitis episodes and high ASOT. Screening with echocardiography is beneficial to improve the detection rates of subclinical RHD in such high-risk populations.