The pain of appendicitis appears first, then disorders of gastrointestinal symptoms. If the disorder first appear, and then the pain, the diagnosis of acute appendicitis recedes into the background. Vomiting may be, but often, the more anacatharsis bring upon the idea of food poisoning. Liquid stool may occur during stimulation offshoot of the rectum, but the diarrhea with pathological impurities also bring upon the idea of the infectious nature of the disease. The newborn the presence of acute appendicitis should lead one to think about Hirschsprung's disease. Differential diagnosis of acute appendicitis in children, even older has fundamental differences from that of adults. Because acute appendicitis in childhood in its clinical presentation (especially with atypical variants of the location of the appendix) is similar to the huge number of diseases not requiring surgery. Even more diseases, both somatic and surgery with the localization in the abdominal cavity and outside it, "disguised" under acute appendicitis. Children should never rely on the limitation of inflammatory process in the appendix. It is important to promptly comply with all the necessary clinical trials, involving the need to consult physicians related specialties (pediatrics, infectious disease, otolaryngologist). There is rarely enough 2 - 6 h of active cases, these terms can be changed. The complexity of determining the children explained by the fact that, depending on age changes and the spectrum of diseases that need to differentiate between acute appendicitis. In children, the older age group the clinical picture of acute appendicitis often simulate disease of the gastrointestinal tract, bile excretion, and urinary systems coprostasia, acute respiratory viral diseases, pneumonia, diseases of the genital organs in girls, congenital and acquired diseases ileocecal angle, childhood infections, illness Schönlein - Schönlein. In children, the first 3 years of life differential diagnosis often carried out with the acute respiratory viral infections, coprostasia, urological diseases, pneumonia, diarrheal diseases, otitis, childhood infections. Errors due to a lack of awareness of options for the clinical course of acute appendicitis, and the difficulty of recognizing this illness in children, especially young children. Application of objective methods of research in the preoperative diagnosis of suspicious clinical signs of appendicitis can be reduced to a minimum percentage of hypo-and giperdiagnosticheskih errors and therefore much to reduce the number of unnecessary appendectomies. With such a strategy reduces the likelihood of postoperative complications and improved detection of diseases that cause abdominal pain.