Background: Peripheral arterial disease (PAD) is a common complication of diabetes mellitus and contributes to impaired wound healing and diabetic foot complications. Colour Doppler ultrasonography provides anatomical and haemodynamic information about lower-limb arteries, while the ankle–brachial index (ABI) is a commonly used screening tool. Aim: To evaluate Colour Doppler findings in patients presenting with diabetic foot, assess the distribution and severity of lower-limb arterial disease, examine its association with Wagner grade, and compare Doppler findings with ABI. Materials and Methods: This hospital-based cross-sectional observational study included 150 patients with diabetic foot attending the Department of Radiodiagnosis at a tertiary-care hospital. Bilateral lower-limb arterial assessment was performed using B-mode, colour-flow and spectral Doppler ultrasonography. Arterial stenosis, waveform patterns and haemodynamic parameters were evaluated. ABI findings were compared with Colour Doppler findings, and associations with clinical variables were analysed. Results: The mean age was 57.3 ± 10.4 years, and 64% of participants were male. Colour Doppler identified PAD in 84 patients (56%). Distal arteries, particularly the dorsalis pedis and posterior tibial arteries, demonstrated substantial stenotic involvement. Dorsalis pedis artery stenosis increased significantly with Wagner grade. Conclusion: Colour Doppler ultrasonography identified PAD in 56% of patients with diabetic foot, with substantial distal arterial involvement. It demonstrated significant associations between arterial stenosis and Wagner grade and may complement ABI in evaluating lower-limb arterial disease.