Background: Acute glomerulonephritis (AGN) occurs in all age groups and any settings around the world. AGN is a major cause of illness and death in children. However, the signs and symptoms are not specific for the disease. Objective: To study the treatment and outcome of Acute Glomerulonephritis in children, at Pediatric ward, Mahosot Hospital Methodology: A retrospective study was conducted to review the medical records of inpatients admitted to the Pediatric Ward at Mahosot Hospital from January 2014 to January 2017. All patients aged 15 years old or younger with complete medical records were included in the study. The information on signs and symptoms, laboratory results, treatment and outcome of the patients with acute glomerulonephritis were descriptively analyzed and reported. Finding: There were 3,528 patients admitted to the Pediatric Ward at Mahosot Hospital during the three years. Among these, 64 patients were diagnosed as having AGN (1.81%), but only 36 cases met the study inclusion criteria. The proportion of males was slightly higher than females (ratio 1.2:1) with the mean (SD) age of 9.6 (±2.7 years old) years old. More than a half (53.57%) of the patients reported a medical history of pharyngitis or tonsillitis. The most common presenting symptoms and signs were edema (94%), hematuria (25%), anuria (36%) and hypertensive emergency (17%). The key abnormally elevated renal function tests included BUN (44%) and creatinine (28%). The most common complications included hypertensive encephalopathy (25%) and congestive heart failure (8%). Conclusion AGN is the major cause of acute kidney injury, congestive cardiac failure and hypertensive encephalopathy, which require optimal treatment in order to have a good outcome.