Objective To analyze CT morphologicl characteristics of tibial nerve,lateral and medial plantar nerves and their clinical significances in the diabetic foot (DF) patients.Methods Bilateral feet (DF group) of 33 patients diagnosed as type 2 diabetes mellitus with DF were examined with CT.Meanwhile,36 uninjured feet (NDF group) of patients with single-side foot wound were taken as the controls.CT findings of distal part of tibial nerve,medial plantar nerve and lateral plantar nerve on the same plane were observed with CT post-processing technique.The morphological measurements were done at the points of A1 (tibial nerve measuring position),A2 (proximal part of medial plantar nerve measuring position),A3 (distal part of medial plantar nerve measuring position) and A4 (lateral plantar nerve measuring position).Both of the anteroposterior and transverse diameters were measured and compared between DF and NDF groups.Results Plantar nerves (tibial nerve,medial plantar nerve and lateral plantar nerve) of DF patients were thick (52/66,78.79 ％),and the edges of nerve were indistinct (51/66,78.78％).The anteroposterior and transverse diameters of measurement points A1,A2 and A4 in DF group were larger than those in NDF group (all P＜0.01).There was no statistical difference of the anteroposterior and transverse diameters of point A3 between the two groups (both P＞0.05).Conclusion The plantar nerves of DF patient were thick with indistinct edges.The observation of continuous morphological characteristics and the diameter measurements of the plantar nerve can be performed with CT post-processing technique,which can provide more information for clinical diagnosis of DF.