Objective To investigate the dynamic changes and influencing factors of kinesiophobia in patients with acute myocardial infarction （AMI），and to provide reference for targeted intervention. Methods A longitudinal survey was conducted during hospitalization (T0)，1 month （T1） and 3 months after discharge (T2) by using a socio-demographic questionnaire，the Tampa Scale for kinesiophobia Heart (TSK-SV Heart)，the Hospital Depression Scale (HAD-D)，the Self-efficiency for Exercise (SEE) and the Exercise Social Support Scale (ESSS). Results A total of 147 patients completed the study. The scores of kinesiophobia were (44.80±6.14) at T0, (42.26±6.06) at T1 and (38.99±5.26) at T2, showing significant difference over time (P<0.05). Stepwise multiple regression analysis showed that kinesiophobia in AMI patients measured at T0 and T2 were associated with age and exercise self-efficacy (P<0.05 for all). Length of hospital stay had significant effect on kinesiophobia measured at T1 and T2 (P<0.05 for all);social support only had significant effect on kinesiophobia measured at T0 (P<0.05), and depression at T1 (P<0.05). Conclusion Kinesiophobia levels in AMI patients showed a decreasing trend after discharge. Medical staff should pay attention to the changing pattern and influencing factors of kinesiophobia, and formulate targeted interventions to promote rehabilitation of AMI patients.