Objective This study aimed to investigate the effect of stage Ⅰ comprehensive cardiac rehabili-tation in patients with acute ST elevation myocardial infarction(STEMI)after emergency percutaneous coronary intervention(PCI).Methods A total of 72 patients with acute ST-segment elevation myocardial infarction combined with PCI admitted to the Department of Cardiovascular Medicine of Beijing Electric Power Hospital of State Grid Corporation from June 2021 to June 2022,which were selected as the research objectsand divided into control group and observation group randomly(36 cases in each group).The control group was treated with routine nursing and health education,and the observation group with stage Ⅰ comprehensive cardiac rehabilitation,including initial assessment(cardiovascular comprehensive assessment),exercise training(exercise training and breathing train-ing),daily activity suggestions and health education,discharge assessment(six-minute walking test and Barthel index assessment).The score of Barthel index(BI)at discharge,the 6-minute walking test distance(6MWD)at discharge,the incidence of major adverse cardiovascular event(MACE)during hospitalization and within one month of discharge,and the length of stay were compared between the two groups.Results After intervention,the six-minute walking test distance(6MWD)and Barthel index(BI)score in the observation group were better than those in the control group,the difference was statistically significant(P<0.05).The incidence of major adverse cardiovascular events(MACE)during hospitalization and one month after discharge was lower in the observation group than in the control group,and the difference was statistically significant(P<0.05).The length of hospital-ization in observation group was lower than that in control groupbut there was no statistical difference(P>0.05).Conclusion The application of phase Ⅰ comprehensive cardiac rehabilitation training in patients with acute ST-segment elevation myocardial infarction combined with emergency PCI could improve the patients'exercise ability,improve their ability of daily activity,reduce the incidence of major adverse cardiovascular events(MACE)in the early stage of the disease,facilitate the patients to return to their families and society as soon as possible,and improve their quality of life.It has high clinical application value.