Objective: The plain film of the abdomen (PAX) is still utilised in the diagnosis of acute appendicitis (Aap). Aim of this study was to evaluate the value of PAX in the diagnosis of Aap in children, since it continues to be a controversial subject. Design: A retrospective study. Setting: Department of Paediatric Surgery, Gazi University Medical School. Patients The histopathological diagnoses and PAX of 213 children (mean age 9-6 years) operated for acute right-lower quadrant pain were evaluated retrospectively. There were 181 patients with Aap and 32 with normal appendix. Methods: The rate of detection of overall thirteen roentgenographic criteria defined in various reports in medical literature as indicating appendicitis were noted and compared with histopathological diagnoses. The PAX which revealed one or more of these signs in combination was considered to be positive for Aap. Data was analysed statistically and sensitivity, specificity and positive and negative predictive values of PAX in the diagnosis of Aap were determined. Results: Roentgenographic sign(s) were detected in 170 (79%) cases, 18 without Aap. The most frequent were lumbar scoliosis with left-sided convexity (50%) and small intestinal air-fluid levels (32%). In 39 cases, 25 with Aap, no sign(s) was detected. In all of the perforated cases, at least one of the determined criteria was seen. The percentage of roentgenographic signs found in cases with and without appendicitis was different significantly (p<0.01). The negative predictive value of PAX in the diagnosis of acute appendicitis was 32.5% and positive predictive value was 89%. Conclusion: PAX could he helpful in diagnosis in children with suspected acute appendicitis.