COVID-19 (coronavirus disease 2019) in children is relatively mild, so it is easy to make a misdiagnosis in the early stages if it presents only with respiratory symptoms. At the time of the pandemic, testing for SARS-CoV-2 is important in all paediatric patients who have fever and acute abdominal pain with diarrhoea or vomiting, to differentiate acute COVID-19 or possible multisystem inflammatory syndrome in children (MIS-C) from acute appendicitis, and thus avoiding unnecessary surgery. On the other hand, early accurate diagnosis and consequent appropriate surgical and antibiotic treatment of appendicitis are important because they can prevent complications such as abscess formation and other postoperative complications. Delayed diagnosis can lead to significant morbidity that can outweigh the damage caused by COVID-19 alone. The fact that at the time of the COVID-19 pandemic radiological examination also has its limitations and can very often show a false-positive finding in children with MIS-C must also be taken into account. It is very important that paediatric surgeons are aware of the gastrointestinal manifestations of acute COVID-19 or MIS-C, and are able to distinguish this new entity from the surgical pathologies it often mimics.