Our study aimed to investigate the ambulatory antibiotics use for acute gastroenteritis in children admitted to the hospital in 1998-2000.The retrospective analysis of medical records was performed in 369 children up to two-years of age; including 87 admitted in 1998, 136 - in 1999 and 146 in 2000 year. Results. Antimicrobials use decreased year after year. In 1998 the antibiotics therapy was included in 44.9% of children, in 1999--in 35.3% and in 2000 year in 32.2% (p = 0.02). In 1998 year, the antibiotics were ordered mainly for children diagnosed as bacterial diarrhea (76.9%) compared to viral etiology (18%). In 2000 year the antibiotics were prescribed for viral gastroenteritis twice more often (61.7%) than for bacterial etiology (29.8). Children with acute gastroenteritis and coexistent signs and symptoms were given antibiotics for treatment diarrhea in the similar percentage as those without any: in 1998--54.2 and 45.8%, in 1999--50.8 and 49.2%, in 2000--40.3 and 59.7%, respectively. Microbiologic examination was not performed in any case before treatment.This study demonstrates the discrepancies between recommendations and ambulatory practice in the antibiotic treatment of acute diarrhea in children both before and after implementation the healthcare system reform. Education programs are needed for optimal management of acute gastroenteritis in children including training in necessity of coproculture before prescribing antimicrobials.