【Objective】 To evaluate the efficacy of recombinant human TNK tissue-type plasminogen activator and adenosine injection through guiding in treating acute ST-segment elevation myocardial infarction (ASTEMI) in emergency primary percutaneous coronary intervention (PPCI). 【Methods】 Patients with ASTEMI who chose to receive emergency PPCI were randomly divided into control group and treatment group according to a digital random table method. The control group received conventional treatment of PPCI. If the infarct-related artery (IRA) reached TIMI flow grade 3 after PPCI, the operation was terminated. If TIMI flow was ≤2, then a guide catheter to inject sodium nitroprusside, nitroglycerin, and tirofiban into the coronary artery to improve coronary microcirculation dysfunction (CMD) was applied until the IRA reached TIMI flow grade 3. The treatment group received the conventional treatment of PPCI, and after opening of the IRA during the operation, a guide catheter to inject recombinant human TNK tissue-type plasminogen activator (8 mg) and adenosine (200 μg) into the coronary artery was applied. If the IRA reached TIMI flow grade 3, the operation was terminated. If TIMI flow was ≤2, then adenosine injection was re-applied to improve CMD until the IRA reached TIMI flow grade 3. Observation indicators were as follows: ① myocardial injury indicators: cardiac troponin I (cTnI), creatine kinase isoenzyme (CK-MB), and N-Terminal pro-brain natriuretic peptide (NT-pro BNP) levels before and 12 h, 24 h, 36 h, and 48 h after surgery; ② myocardial perfusion indicators: corrected TIMI frame count (CTFC) after surgery and ST segment regression value (STR) at 90 min after surgery; ③ degree of myocardial ischemia: rest D-SPECT+adenosine stress D-SPECT examination at day 3 after surgery, observation of myocardial perfusion total score under 17 segment distribution and myocardial ischemia total segment number; ④ adverse drug reactions at day 30 after surgery: subcutaneous ecchymosis, gingival bleeding, gastrointestinal bleeding, urinary bleeding, hemoglobin decline, and cerebral hemorrhage; ⑤ major adverse cardiovascular events (MACE) at day 30 after surgery: cardiac death, myocardial infarction, heart failure, and target vessel revascularization. 【Results】 ① Myocardial injury indicators: There was no significant difference in the levels of cTnI, CK-MB, or NT-pro BNP before surgery between the two groups (all P>0.05). The myocardial injury indicators were significantly lower in the treatment group than in the control group at 12 hours after surgery (all P<0.05), and then showed a downward trend. There was no significant difference between the two groups at 48 hours after surgery (all P>0.05). ② Myocardial perfusion indicators: CTFC in the treatment group was significantly better than that in the control group after surgery (P<0.05). Using the rank sum test, the STR was significantly better in the treatment group than in the control group at 90 minutes after surgery (Z=2.437, P=0.014). ③ myocardial ischemia: Both groups underwent rest D-SPECT+adenosine stress D-SPECT examination at 3 days after surgery. Under the distribution of 17 myocardial segments, the total score of myocardial perfusion and the total number of myocardial ischemia segments in the treatment group were significantly better than those in the control group (all P<0.05). ④ Adverse drug reactions 30 days after surgery: There was no significant difference in subcutaneous ecchymosis, gingival bleeding, gastrointestinal bleeding, urinary system bleeding, hemoglobin decline, or cerebral hemorrhage between the two groups (P>0.05). ⑤ MACE 30 days after surgery: There was no significant difference in cardiac death, myocardial infarction, heart failure, target vessel revascularization, or total MACE between the two groups (P>0.05). 【Conclusion】 The intra-coronary injection of recombinant human TNK tissue-type plasminogen activator and adenosine injection through a guiding catheter in emergency PPCI is safe and effective for the treatment of ASTEMI. It can improve myocardial injury, myocardial perfusion, and myocardial ischemia.