Carotid artery Doppler ultrasound is being explored for its potential as a non-invasive tool for evaluating coronary artery disease (CAD) severity and cardiovascular risk. This study aimed to investigate the association between carotid Doppler parameters and CAD severity, as determined by the Gensini score (GS) and multi-vessel disease presence. Ninety patients undergoing coronary angiography (CAG) and carotid ultrasound were retrospectively analysed. Carotid Doppler parameters and CAD severity were assessed through bivariate and multivariable analyses. Among the patients studied, 80% were male, with a mean age of 65.24 years (±9.91). Triple vessel disease (68.9%) and dominant vessel disease (73.3%) were prevalent coronary findings, with a mean GS of 139.2 (±76.6). Increased intima-media thickness (IMT) in the common carotid artery (CCA) and internal carotid artery (ICA) showed significant associations (CCA IMT: OR = 0.312, p = 0.037; ICA IMT: OR = 0.354, p = 0.017) with high GS (>125) and multi-vessel disease. Significant carotid stenosis (>50% diameter stenosis) emerged as an independent predictor of CAD severity. Fibrocalcific plaques, detected in 62.2% of cases, correlated significantly with elevated GS. Plaque burden, especially plaques in >3 locations, indicated a higher likelihood of triple vessel disease and a higher GS. Carotid Doppler parameters, particularly IMT and significant stenosis, are robust predictors of CAD severity, including high GS and multi-vessel disease. Integrating carotid artery assessment into clinical protocols can aid in timely interventions and preventive strategies for CAD management.