Recent studies estimated that about 20–30% of visits in a paediatric emergency department (PED) are inappropriate. Nonurgent visits have been negatively associated with crowding and costs, causing longer waiting and dissatisfaction among both parents and health workers. We aimed to analyze possible factors conditioning inappropriate visits and misuse in a PED. We performed a cross-sectional study enrolling children accessing an Italian PED from June 2022 to September 2022 who received a nonurgent code. The appropriateness of visits, as measured by the “Mattoni SSN” Project, comprises combination of the assigned triage code, the adopted diagnostic resources, and outcomes. A validated questionnaire was also administered to parents/caregivers of included children to correlate their perceptions with the risk of inappropriate visit. Data were analyzed using independent-samples t-tests, Wilcoxon-Mann–Whitney tests, chi-square tests, and Fisher’s exact tests. The factors that were found to be associated with inappropriate visits to the PED were further evaluated by univariable and multivariable logistic regression analyses. Almost half (44.8%) of nonurgent visits resulted inappropriate. Main reasons for parents/caregivers to take their children to PED were (1) the perceived need to receive immediate care (31.5%), (2) the chance to immediately perform exams (26.7%), and (3) the reported difficulty in contacting family paediatrician (26.3%). Inappropriateness was directly related to child’s age, male gender, acute illness occurred in the previous month, and skin rash or abdominal pain as complaining symptoms.