Introduction. The typical clinical picture of acute appendicitis (AA) is absent in most of patients, that lead for the high frequency of misdiagnosis with the increase of complicated forms of AA. Due to that, it is necessary to establish the new available laboratory markers, which permitted with the high level of reliability distinguish children not only with AA, but also is appendix perforation. The question what method of appendectomy should be choose – the conventional or mini-invasive – are still under debate. Aim of the study was to summarize the results of diagnosis and treatment of AA in children with the applying of various laboratory markers, ultrasonography (US), and laparoscopy. Materials and methods. This study based on the results of surgical treatment of 3171 children with AA, which were operated during 2009–2018 years. Diagnosis was established on the data of anamnesis, results of objective and laboratory investigation. US was performed in 1183 (37.3%) of patients. Open appendectomy (OA) was performed in 2879 (90.8%) and laparoscopic (LA) – in 292 (9.2%) of patients. With the aim to evaluate the results the methods of variative statistic, determination of specificity, sensitivity, positive (PPV) and negative (NPV) predictive value, etc. were applied. Results. Among the laboratory markers, the best results for the diagnosis of AA showed the neutrophil to lymphocytes ratio (NLR) with the sensitivity – 84.9%, specificity – 67.1%, PPV – 17.8%, and NPV – 98.9%. NLR (sensitivity – 82.5%, specificity – 84%, PPV – 98.5%) and sodium blood level (sensitivity – 90.3%, specificity – 89.9%, PPV – 98.9%) had the best results for the diagnostic of perforated AA. US is the important compound of diagnostic of AA in children with the high level of sensitivity, specificity, PPV, and NPV – 93%, 85%, 86%, and 92%, correspondingly. By the frequency of complications in the early postoperative period, OA and LA had no statistically significant differences, but at follow-up after surgery, LA revealed the sufficient advantages over OA. Conclusions. Among the various laboratory markers, NLR had the better prognostic value for the diagnosis of AA and indices of plasma sodium concentration and NLR for the preoperative diagnosis of perforated appendicitis. US with the high degree of reliability allows to confirm or exclude the diagnosis of AA in children with acute abdominal syndrome. Laparoscopic appendectomy is the real alternative for conventional methods of AA treatment. Besides of the well-known advantages of mini-invasive surgery, the laparoscopic appendectomy had an advantage at the follow-up period. No conflicts of interest was declared by the authors. Key words: acute appendicitis, children, diagnostic, treatment, laparoscopy.