Objective To investigate the association between the P-wave terminal force in lead V1 (PtfV1) and prognosis in the electrocardiogram (ECG) of the acute coronary syndrome (ACS) patients. Methods A total of 308 ACS patients were selected from Cadre′s Ward and the Departments of Cardiology of Beijing Aerospace Hospital, during May 2017 and June 2018. All patients underwent electrocardiogram examination, and they were divided into 3 groups according to the value of PtfV1:PtfV1<20mm·ms group (n=106), 20mm·ms≤PtfV1≤40mm·ms group (n=100) and PtfV1>40mm·ms group (n=102). All of the patients were followed up for at least 6 months. The clinical data and the incidences of major adverse cardiovascular events (MACEs) were compared in the 3 groups. SPSS statistics 20.0 was used for data analysis, and Kaplan-Meier survival analysis was applied to analyze the differences in survival rates between non-MACEs patients of the 3 groups. Results During the follow-up of 6-30 (12.5±7.2) months, the incidence of MACEs was 1.89% (2 cases) in the PtfV1<20mm·ms group, 7.00% (7 cases) in the 20mm·ms≤PtfV1≤40mm·ms group and 11.76% (12 cases) in the PtfV1>40mm·ms group. Kaplan-Meier analysis showed that significant difference were seen in the survival rate among the 3 groups (Chi-square=8.152, P=0.017), with that of the PtfV1<20mm·ms group obviously lower than that of the PtfV1>40mm·ms group (Chi-square=8.079, P=0.004). Conclusion PtfV1 is associated with the incidence of cardiovascular events in ACS patients, and can be used as a predictor for prognosis and the incidence of long-term cardiovascular events.