Background: Atherosclerosis is a progressive vascular condition that remains a leading cause of morbidity and mortality worldwide. Cigarette smoking is an established risk factor for vascular endothelial damage and accelerates atherosclerotic changes through both direct and indirect mechanisms. The carotid arteries, being superficial and accessible, serve as a valuable window for early detection of systemic atherosclerosis. High-resolution Doppler ultrasonography (USG) allows for non-invasive evaluation of both morphologic and hemodynamic parameters of the carotid arterial system, including intima-media thickness (IMT), plaque formation, luminal narrowing, peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI). Comparing these parameters between smokers and non-smokers offers insight into the early vascular changes induced by tobacco exposure. Aim: To assess and compare the morphologic and hemodynamic parameters of the carotid arteries using Doppler ultrasonography in smokers and non-smokers. Materials and Methods: This cross-sectional observational study was conducted on 100 adult subjects aged 30�60 years, comprising 50 chronic smokers (�10 pack-years) and 50 age-and sex-matched non-smokers. All participants underwent B-mode and color Doppler ultrasonography of bilateral common carotid arteries (CCA), carotid bulb, and internal carotid arteries (ICA). Morphologic evaluation included assessment of intima-media thickness, presence of plaques, and arterial wall echotexture. Hemodynamic parameters including PSV, EDV, and RI were measured in the CCA and ICA. Statistical comparison between the two groups was done using unpaired t-test and chi-square test, with p-value <0.05 considered significant Results: The mean IMT in smokers was significantly higher compared to non-smokers (0.82 ± 0.09 mm vs. 0.66 ± 0.07 mm, p < 0.001). Carotid plaques were detected in 34 of smokers and only 6 of non-smokers. Hemodynamically, smokers demonstrated elevated peak systolic velocities and resistive indices in both CCA and ICA, indicating increased vascular resistance. The mean CCA PSV in smokers was 96.3 ± 12.8 cm/s compared to 81.7 ± 10.4 cm/s in non-smokers (p < 0.001). A statistically significant difference in ICA RI values was also noted (0.78 ± 0.06 in smokers vs. 0.70 ± 0.05 in non-smokers, p < 0.001). Conclusion: Doppler USG effectively demonstrates early structural and functional changes in the carotid arteries associated with smoking. Increased intima-media thickness, higher resistive indices, and greater plaque prevalence among smokers indicate early vascular aging and subclinical atherosclerosis. Routine Doppler screening in chronic smokers could aid in early identification of vascular risk, allowing timely lifestyle modifications and therapeutic interventions. © 2025 Elsevier B.V., All rights reserved.