Objective: To delve into the merit of employing speckle tracking imaging (STI) for procuring left ventricular function metrics in assessing coronary artery disease (CAD) without regional wall motion abnormalities (RWMA). Methods: A combined tally of 175 patients subjected to coronary angiography (CAG) in the Central Hospital of Dalian University of Technology from December 2023 to August 2024 were selected. As suggested by the findings derived from CAG, the patients were divided into three groups by the Gensini scoring system: the mild stenosis group (n = 58, Gensini score ≤ 28), the moderate stenosis group (n = 54, Gensini score > 28 and < 55), and the severe stenosis group (n = 63, Gensini score ≥ 55). In addition to conventional ultrasound measurements of cardiac parameters, global work efficiency (GWE), global myocardial work index (GWI), global longitudinal strain (GLS) were measured. Results: No statistical contrast came to light in the general baseline specifics among mild, moderate, and severe stenosis groupings (all P-values exceed 0.05); Data validated striking divergences in LVEF, GLS, GWI, and GWE across the three groups (all P-values below 0.05), the absolute values of these parameters demonstrated a significant reduction in the severe stenosis group (P-value below 0.05). GWE, GWI, GLS, and LVEF illustrated a dramatic link with the Gensini score (P-value below 0.05). ROC curve analysis demonstrated that GLS had better sensitivity, while GWE exhibited higher specificity. Conclusion: STI can evaluate left ventricular function without RWMA in CAD patients, and has predictive value for severe CAD.