〔Abstract〕 Objective To investigate the influencing factors of deterioration after improvement of recombinant tissue plasminogen activator (rt-PA) intravenous thrombolysis in patients acute cerebral infarction (ACI). Methods A total of 260 ACI patients who were improved after rt-PA intravenous thrombolytic therapy were selected from December 2018 to December 2019 in Jiaozuo Hospital of Traditional Chinese Medicine. Patients were followed up for 3 months after rt-PA intravenous thrombolytic therapy. The incidence of deterioration after improvement was recorded, and the patients were divided into the occurrence group and the non-occurrence group. To analyze the factors affecting the occurrence of deterioration after improvement of rt-PA intravenous thrombolysis in ACI patients. Results Among 260 ACI patients, 35 cases (13.46%) had deterioration after improvement of rt-PA intravenous thrombolysis. The proportion of patients with underlying diseases in the occurrence group was higher than that in the non_x0002_occurrence group, the thrombolysis time was longer than that in the non-occurrence group, the score of National Institutes of Health Stroke Scale (NIHSS) was higher than that in the non-occurrence group, and the level of white blood cell count (WBC) was higher than that in the non-occurrence group, the differences were statistically significant (P < 0.05). Logistic regression analysis showed that combined underlying diseases, long thrombolysis time, high NIHSS score at admission and high WBC level were all risk factors for deterioration after improvement of rt-PA intravenous thrombolysis in ACI patients (P < 0.05). Conclusion Combined basis diseases, long thrombolysis time, high NIHSS score at admission, and high WBC level are the influencing factors of the deterioration after improvement of rt-PA intravenous thrombolysis in ACI patients.