Introduction: Estimating the age of the ossification of the iliac crest may help determine the legal age. For this purpose, both anthropological and radiological methods (conventional radiography, ultrasound, Tomography, and MRI) have been used to study different systems. Objectives: The present study aimed to to evaluate the iliac crest apophysis for age estimation through multidetector computed tomography (MDCT) in 10- to 29-year-old individuals. Materials and Methods: This retrospective study was carried out on 10- to 29-year-old individuals who underwent pelvic CT examinations for different reasons in Imam Khomeini and Golestan hospitals of Ahwaz during 2016–2018. The CT examinations of the iliac crest apophysis of 531 patients (267 females and 264 males) were evaluated based on the Kreitner's four-stage system. Results: According to the Kreitner's four-stage system, the minimum age for both sides of the pelvis at stage 2 for girls and boys was 12 years and 13 years, respectively. However, at stage 3, the minimum age for girls and boys was 15 and 17 years, respectively. Accordingly, stage 4 was first observed in boys at age 17 on both sides of the pelvis. In contrast, it appeared in girls at the age of 20 on the right side. Conclusion: Along with the findings of other studies, the results showed that multidetector computed tomography (MDCT) is recommended for iliac crest in retrospective cases (where pelvic CT scans already exist), and it may be considered as a supportive method for age-estimation purposes. Moreover, when CT images are used along with other age estimation methods, they provide physicians with valuable supplementary information.