Objective: To investigate the evaluation value of cardiac color Doppler echocardiography (CDE) in assessing poor prognosis in patients with coronary atherosclerotic heart disease (CAD). Methods: A retrospective review was conducted of 106 patients with coronary artery disease (CAD) who were treated in the hospital’s cardiovascular department between January 2023 and June 2024. All participants received baseline comprehensive Doppler echocardiography (CDE) assessments. Based on whether they experienced a Major Adverse Cardiovascular Event (MACE) within one year of follow-up, the patients were categorized into either a MACE group or a non-MACE group. The study compared baseline clinical information and CDE parameters, specifically left ventricular ejection fraction (LVEF), wall motion score index (WMSI), and mitral annular E/e’ ratio, between the two groups. Independent predictors of MACE were identified using multivariate logistic regression analysis. Results: A total of 29 out of the 106 patients experienced MACE during the one-year follow-up. Compared with the non-MACE group, the MACE group had a higher prevalence of diabetes mellitus. In terms of CDE parameters, the MACE group had a lower LVEF than the non-MACE group (p < 0.05), while WMSI, average E/e’, pulmonary artery systolic pressure (PASP), and mitral regurgitation (MR) proportion were all higher in the MACE group than in the non-MACE group (p < 0.05). Multifactor logistic regression analysis revealed that after adjusting for confounding factors such as diabetes, WMSI (OR = 3.003, 95% CI: 1.226–7.356, p = 0.016) and mean E/e’ (OR = 1.281, 95% CI: 1.006–1.539, p = 0.008) were independent predictors of the occurrence of major adverse cardiovascular events (MACE). Conclusion: WMSI and E/e’ diagnosed by color Doppler echocardiography (CDE) hold significant and independent assessment value for predicting poor prognosis in patients with coronary artery disease (CAD).