Objective To assess the safety and effectiveness of self-made side hole balloon for treating no-reflow following percutaneous coronary intervention(PCI). Methods Twenty-three patients diagnosed with no-reflow during PCI from Jan. 2012 to Jan. 2013 were enrolled. Residual stenosis, thrombosis,dissection, and spasm of coronary artery were excluded. The mean age of the 23 patients was (62.0±13.8) years old. Of the 23 patients 14 had ST segment elevation myocardial infarction (STEMI), and 9 underwent elective PCI. There were 11 cases with no-reflow in the left anterior descending branch, 8 in the right coronary artery and 4 in the circumflex branch. The drugs (nitroglycerin and tirofiban) were selectively injected into the vessel using self-made side hole balloons. The thrombolysis in myocardial infarction (TIMI) grade before and after procedure,ST segment resolution (STR),ST-T changes for 24 and 72 hours and complications (perforation, dissection,and thrombosis of coronary artery) were observed postoperatively. Patients were followed up by ECG and echocardiogram at 1 month after PCI. Incidence of major adverse cardiovascular events (MACEs) and cardiac function were observed 6 months after PCI. Results After intracoronary administration of drug therapy, TIMI grade-1 flow was found in 3 patients, TIMI grade-2 flow in 5 patients and TIMI grade-3 flow in 15 patients. In patients with STEMI, complete resolution (≥70%) was found in 8 patients,partial resolution (30%-69%) in 4, and no resolution (<30%) in 2. One of the 2 patients with ventricular electrical storm was treated with temporary cardiac pacing and drug therapy and recovered within 1 week; the other one with pericardial tamponade who was treated with emergency surgery repair died. In 9 patients undergoing selected PCI,transient ST segment changes were noted in 3 patients which recovered within 1 week after conservative treatment; with no perforation, dissection,or thrombosis of coronary artery. One month after discharge, echocardiogram of the 22 patients showed a mean left ventricular ejection fraction (LÜEF) of (50.6±14.3)% and a fractional shortening in the short axis view of 0.36±0.04, and ECG showed non-specific changes of ST-T in 6 patients. In 4 patients with STEMI, culprit artery showed TIMI grade-3 by angiography performed during PCI for non-culprit vessel 1 month after primary PCI. At 6 months after primary PCI, there was no MACE; 18 patients were in New York Heart Association Class Ⅰ and 4 in Class Ⅱ. Conclusion Self-made side hole balloon is a safe, economical, effective and convenient method for intracoronary administration of nitroglycerin and tirofiban in treating no-flow during PCI, but the result still needs further verification.