Еxamined 43 children with inflammatory bowel disease (IBD). IBD activity, except clinical and endoscopic manifestations of the disease was evaluated in terms of total protein, g-globulin, immunoglobulin (Ig) G, A, M, fibrinogen, soluble fibrin monomer complexes (SFMC), C-reactive protein (CRP), serum. All children per formed a serological examination of blood by ELISA for antibodies to herpes simplex virus types 1—2 (HSV1—2), Epstein-Barr virus (EBV), cytomegalovirus (CMV), herpes zoster virus (VZV). All patients underwent determination of specific DNA HSV1—2, herpes virus type 6 (HHV6), CMV and EBV in blood cells and/or intestinal biopsies using PCR. 25 children held definition of indicators of interferon (IFN). Set imbalance of IFN, characterized by increased levels of serum IFN-induced synthesis and decreased blood cells IFNa and IFNg. Active herpes virus infection in children with IBD occurred in 88.4% of cases. In 30.2% of cases were determined monogerpesvirusnye infection in 58.1% of cases — mikstgerpesvirusnye active infection. Laboratory indicators of activity in IBD were significantly higher in children with active herpes virus infection, indicating that the negative effects of chronic active herpesvirus infections on the course of IBD in children.