Introduction :   : Infective endocarditis is a disorder with high mortality and morbidity  in children specially in whom with Congenital Heart Disease(CHD) .The target of our study is a description  of the factors affecting  pediatric Infective endocarditis  particularly in whom with CHD  in Mashhad.
 
Method :   this cross-sectional  study  includes 19 patients less than 18 years old  with endocarditis  hospitalized in the Department of Pediatric Cardiology( University of Mashhad Medical Sciences) between 1381 to1391.Clinical symptoms, risk factors, underlying  heart disease ,laboratory- echocardiogeraphic results were studied. Finally data were  analyzed by using SPSS 16 software.
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Results: Endocarditis  were seen in 21.1% of children with previous underlying infectious disease. According to results of blood cultures Staphylococcus aurous was the most common crime ( 21%).Each of  Coagulase-negative staphylococci, Staphylococcus epidermidis and gram-negative cocci were seen in just one patient.10.6% of children had Umbilical /vein catheter history. The most common underlying factor was congenital heart disease (47.7%). Having history of surgery in 7(36.8%) patients due to CHD before endocarditis were detected .Vegetation were  resected in 2 (10.5%)children  as a treatment after endocarditis .There was no significant difference between time of surgery and microbial crime(p-value= 0.069). Cardiac vegetation was seen in 18 children(94.7%).One child (5.2%) died.
Conclusion: According to irrecoverable effects of infectious endocarditis in children, it seems that strong clinical suspicion also considering of  underlying causes and negative results of blood cultures , especially in children with congenital heart disease can be crucial in  reducing mortality and complications of infectious endocarditis.