Objective To explore the risk factors of heart failure（HF）in patients with ST⁃segment elevation myocardial infarction（STEMI）after primary percutaneous coronary intervention（PPCI）during hospitalization. Methods The medical data on 118 patients with STEMI who had undergone PPCI from June 2018 to May 2020 were collected in our hospital. The patients were divided into HF group（n = 58）and non⁃HF group（n = 60）. The relationship between the influencing factors and the occurrence of HF was analyzed. Results The percentage of diabetes and multi ⁃vessel lesions，and levels of HbA1c，fasting blood glucose，BNP and cTnI peak were signifi⁃ cantly higher in HF group than in non⁃HF group（P < 0.05）. The Syntax score was significantly higher and the total ischemic time（TIT）was markedly longer in HF group than in non⁃HF group（P < 0.05 for both comparisons）. The multivariate binary logistic regression analysis showed that Syntax score ，multi⁃vessel lesions ，and TIT were independent risk factors of HF in patients with STEMI during hospitalization after PPCI（P < 0.05），whereas hemo⁃ globin was a protective factor of HF. The ROC curve showed that Syntax score and TIT could be used as predictors of HF. The AUC were 0.877 and 0.786，the best cut⁃off point was 18.5 points and 221.5 min，the sensitivity was 89.7% and 91.4%，and the specificity was 68.3% and 55.0%. Syntax score combined with TIT was also used as pre⁃ dictor of HF，and the AUC was 0.922. Conclusions Patients with higher Syntax score，multi⁃vessel lesions，and longer TIT were more likely to develop HF during hospitalization after PPCI. Hemoglobin was a protective factor. Combination of Syntax score with TIT had higher predictive value for HF patients with STEMI after PPCI during hospitalization.