Objective. To investigate the predictive value of thromboelastography for the occurrence of early neurological deterioration (END) in patients with primary acute cerebral infarction (ACI). Methods. 150 patients who were hospitalized in the department of neurology of our hospital from September 2020 to September 2021 and were clearly diagnosed with primary ACI by head CT and head magnetic resonance imaging (MRI) were selected and divided into END and non-END groups according to the change in National Institute of Health Stroke Scale (NIHSS) score within 72 h of admission. The general baseline data and laboratory indexes of the first examination at admission were compared between the two groups, and the factors that may affect the occurrence of END were determined by univariate analysis and multivariate logistic regression analysis, and the predictive value of thromboelastography on the occurrence of END after ACI was analyzed by applying the receiver operating characteristic (ROC) curve. Results. Time to onset, baseline NIHSS score, percentage of diabetes, white blood cell (WBC) levels, C-reactive protein (CRP), and apolipoprotein B (Apo B) levels were higher in the END group than in the non-END group (
P
<
0.05
); coagulation reaction time (RT) (3.97 ± 1.16 vs. 5.49 ± 1.03) and kinetic time (KT) (1.32 ± 0.67 vs. 1.82 ± 0.58) were lower in the END group than in the non-END group (
P
<
0.05
). Inthe END group (
P
<
0.05
) diabetes, baseline NHISS score, CRP level, Apo B level, and RT were independent risk factors for the development of END in patients with ACI (
P
<
0.05
). The AUC of RT to predict the occurrence of END in patients with ACI was 0.855 (95% CI: 0784 to 0925,
P
=
0.001
), with a sensitivity of 81.70% and specificity of 78.00% when the optimal cut-off value was 0.597. Conclusion. NIHSS score at admission, CRP, apolipoprotein B, RT shortening, and diabetes mellitus were independent risk factors for the development of END in ACI patients; RT shortening in TEG was predictive of END in ACI patients.