Objective To explore the role of myocardial strain parameters in predicting left ventricular remodeling (LVR) in patients with acute ST segment elevation myocardial infarction (STEMI).Methods A total of 81 patients who were diagnosed with STEMI and successfully treated with primary percutaneous coronary intervention (PPCI) in Cardiovascular Clinic of Shanghai Jiao Tong University Affiliated Sixth People's Hospital from Jan. 1, 2018 to Jan. 31, 2019 were sequentially enrolled. Cardiac magnetic resonance at 3.0 Tesla was performed at the acute stage of STEMI (< 7 d) and after 6 months of onset. According to whether LVR (increase of left ventricular end-diastolic volume [LVEDV] measured by the second cardiac magnetic resonance examination ≥20% from baseline) occurred after 6 months of onset, the patients were divided into LVR group (33 cases) and non-LVR group (48 cases). Myocardial strain parameters were evaluated to predict LVR of STEMI patients after PPCI.Results Compared with the non-LVR group, the level of peak hypersensitive serum cardiac troponin I (peak hs-cTnI) at the acute stage of myocardial infarction was significantly higher, the global longitudinal strain (GLS) was significantly lower, and the time to peak longitudinal strain in infarct zone was significantly shorter in the LVR group (all P < 0.01). Multivariate logistic regression analysis showed that peak hs-cTnI (odds ratio [OR]＝1.026, 95% confidence interval [CI] 1.006-1.046, P＝0.012) and time to peak longitudinal strain in infarct zone (OR＝0.967, 95% CI 0.950-0.983, P < 0.001) were independent influencing factors of LVR after 6 months of onset in STEMI patients. ROC curve analysis showed that when the peak hs-cTnI was 85.54 μg/L, the sensitivity and specificity of predicting LVR in STEMI patients after 6 months of onset were 60.60% and 97.90%, respectively (area under curve [AUC] value was 0.795, P < 0.001); when the GLS was －10.56%, the sensitivity and specificity were 81.80% and 70.80%, respectively (AUC value was 0.761, P < 0.001); when the time to peak longitudinal strain in infarct zone was 309.12 ms, the sensitivity and specificity were 87.90% and 87.50%, respectively (AUC value was 0.926, P < 0.001).Conclusion Peak hs-cTnI at acute stage, GLS and time to peak longitudinal strain in infarct zone were valuable in predicting LVR in STEMI patients receiving PPCI treatment after 6 months of onset, and peak hs-cTnI and time to peak longitudinal strain in the infarct zone are independent influencing factors for LVR.