Background: The aim of this study was to prove the reliability of plantar fascia MDCT thickness measurement in plantar fasciitis diagnosis, using US as an standard. Methods: We enrolled 110 participants (80 patients and 30 healthy controls). The patients who had painful heel and admitted to the clinic of the Rheumatology then sent to the Radio-diagnosis department. Adult patients with uni/bilateral heel pain considered as inclusion criteria. Exclusion criteria involved the open wound, foot fracture and infection. All participants underwent the steps: history taking, clinical examination and then examined at the same day by US and 128-MDCT. Results: Plantar fasciitis diagnosis by MDCT showed good sensitivity and diagnostic accuracy values. In our study increased plantar fascia thickness was reliable outcome in all patients with the clinical diagnosis of plantar fasciitis. Results revealed that the plantar fascia thickness by US for patients group was 5.65±1.23 mm. We illustrated that the plantar fascia thickness by MDCT for patients group was 5.24±1.20 mm. Our results of small bias and variability measures regarding plantar fascia thickness in plantar fasciitis patients by MDCT considered a good indicator of reliability. Conclusion: In previous literatures, US was the first imaging modality as its availability, least cost and lack of radiation. However, US couldn’t evaluate the bony lesions, operator dependent, require prone position (uncomfortable). From these weak points, we searched for another imaging modality which had the same accuracy of US in diagnosis and could manage the mentioned weak points. MDCT was a reliable imaging tool for depiction and measurement the plantar fascia thickness.