Background: One of the common clinical issues in ENT practice is chronic tonsillitis. The major germ that causes tonsillitis to recur frequently is streptococcus. A tonsillectomy is the best option if medical therapy has failed. High antistreptolysin O (ASO) titer levels were observed in several patients who presented with recurrent tonsillitis attacks. Group A beta hemolytic streptococcal (GABHS) tonsillitis may be accompanied by severe consequences such glomerulonephritis and rheumatic fever. The aim of study: To assess how tonsillectomy will affect an increased ASO titer in pediatric patients. Patients and methods:  65 patients who were eligible for tonsillectomy participated in a prospective, non-randomized clinical research. There were 35 females and 30 males, ranging in age from 3 to 16. All patients having a positive throat swab for group A beta hemolytic streptococcal (GABHS) and an elevated ASO titer level (equal or above 200 IU/ml). Following surgery, follow up is done after 1, 3, and 6 months. Results: First, third, and sixth month post-operative ASO titer means were all significantly lower than preoperative ASO titer means, p 0.001. Conclusion: Tonsillectomy significantly lowers the level of ASO titer.