BACKGROUND: Left ventricular (LV) thrombus formation is a common complication of anterior myocardial infarction (ANT-MI). The aim of this study was to investigate the relationship between apical longitudinal strain (ALS) and LV apical thrombus after ANT-MI. METHODS: The cross-sectional study included a total of 235 patients who were followed up after primary percutaneous coronary intervention performed for ANT-MI and had a reduced LV ejection fraction (LVEF) (< -40%). Of these patients, 24 were excluded from the study, and the remaining 211 patients were included in the analysis. Patients were divided into two groups based on the presence (n = 42) or absence (n = 169) of LV thrombus detected by echocardiography. ALS was measured using speckle-tracking echocardiography. RESULTS: Thrombus was detected in 42 of 211 patients. There was no significant difference between the groups regarding age or gender. Apical strain (AS), global longitudinal strain (GLS), apical wall thickness (AWT), and EF were significantly lower in patients with LV apical thrombus when compared to those without LV apical thrombus (AS, -5.00 +- 2.30% vs. -8.54 +- 2.48%, p < 0.001; GLS, -10.6 +- 3.54% vs. -12.1 +- 2.84%, p = 0.013; AWT, 4.71 +- 1.11 vs. 6.33 +- 1.78 mm, p < 0.001; EF, 31.40 +- 4.10% vs. 37.75 +- 3.17%, p < 0.001). On univariate and multivariate analyses, aneurysm (AA), AS, and AWT were found to be independent predictors of LV apical thrombus (AA, odds ratio [OR] 4.649, p = 0.010; AS, OR 1.749, p < 0.001; AWT, OR 0.729, p = 0.042). CONCLUSION: ALS is highly sensitive and specific for predicting LV thrombus after ANT-MI. An early and accurate evaluation of LV thrombus may prevent embolic complications, particularly cerebrovascular events.