Background: Many problems in the diagnosis of patients with suspected appendicitis have led to the design of clinical scoring systems. In children, diagnostics tools for appendicitis are more critical. Younger patients, diagnostic challenges become more. Practical scoring systems are useful without any particular material and necessitate novel ability. Objectives: However, in spite of the reported outstanding consequences, these scoring systems are not employed regularly. Methods: In this cross-sectional study performed from October 2016 to October 2017, ten provinces out of the 31 provinces in Iran were randomly selected. A total of 631 patients referring to the hospitals with the suspicion of acute appendicitis were assessed. Related variables such as age, sex, right lower quadrant (RLQ) pain, migration of pain to RLQ, nausea, and presence of vomiting, anorexia, tenderness in RLQ and guarding, presence of rebound tenderness, and degree of fever were taken from recorded files by pediatricians. Alvarado scoring system was used for included cases to assess the accuracy of this test for diagnosis of appendicitis in our centers. Results: The mean age of eligible patients was 9.3 ± 3.21 years ranged from 3 years to 18 years, and 380 (60.5%) were male. Using the Alvarado score system in this study, considering the cut-off point value of 7 to decide for operation, the positive predictive value (PPV) showed 32.6%, and negative predictive value (NPV) was 76.73%, with a sensitivity of 44.05% and, specificity of 66.95%. There were statistically no significant correlations among the scoring of the Alvarado and diagnosis of AA (P < 0.05). Regarding receiver operator characteristic curves (ROC), the area under curve (AUC) was 0.58 (0.54 to 0.63) for Alvarado. The AUC was very low, so there was no value for the diagnosis of appendicitis. According to the findings of the present study, the cut-off point of 4.5 is suggested for the diagnosis of acute appendicitis in children with a sensitivity of 73% and specificity of 58%. Conclusions: Although the Alvarado scores supply obviously practical diagnostic information in the management of pediatric population with supposed appendicitis, this method delivers no adequate PPV for clinical practice as a safe way for determining necessary operation.